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  • PHP "You have () new comments on your clip", how?

    - by user292516
    Hello. I want to do a function to my users, so on index.php there is e.g: You have 2 new comments on your clip How should i do this? I mean i want ideas to do this the easiest way. Table for the videos is member_videos, and tables for the comment is member_videocomments, a comment inside the table is connected by their "videoID", which is the id of the column in member_videos. Should i do the classic, making a field, which all is 0, until it has been seen by the user its 1 or what should i do.

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  • How do I use 2 include statements in a single MVC EF query?

    - by alockrem
    I am trying to write a query that includes 2 joins. 1 StoryTemplate can have multiple Stories 1 Story can have multiple StoryDrafts I am starting the query on the StoryDrafts object because that is where it's linked to the UserId. I don't have a reference from the StoryDrafts object directly to the StoryTemplates object. How would I build this query properly? public JsonResult Index(int userId) { return Json( db.StoryDrafts .Include("Story") .Include("StoryTemplate") .Where(d => d.UserId == userId) ,JsonRequestBehavior.AllowGet); } Thank you for any help.

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  • Should i keep #wrapper{ width:100%} in print css?

    - by metal-gear-solid
    Should i keep #wrapper{ width:100%} in print css? because on screen my design is a fixed width design 960 px. but there are so many paper type and sizes in the world and anybody can take print on any size paper, bigger and smaller. So if in print css i do not specify relative width then i think print of page will cut of from right size if user will take print on the paper size which can smaller or larger width than my site #wrapper width (960px). then it can create problem. http://www.dpandi.com/paper/index.html printer also leave some margin when printing. So should keep everything is relative size in print css?

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  • Floating toolbar on bottom, centered, 80% of current screen width

    - by Tom
    I'm trying to implement a Facebook like toolbar on the bottom of the screen for a website I'm currently working on. Currently, I have it 100% of the width of the screen but I'd like to have it look almost exactly like Facebook's toolbar, centered, bottom justified on top, around 80% of the current screen's width. Here is the current CSS for the toolbar I have that is 100% of the screen's width. Thanks in advance. CSS: <style type="text/css"> #toolbar { background:url('/_assets/img/toolbar.gif') repeat-x; height:25px; position:fixed; bottom:0px; width:100%; left:0px; border-left:1px solid #000000; border-right:1px solid #000000; z-index:100; font-size:0.8em; } </style>

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  • Why does SQL Server consider N'????' and N'???' to be equal?

    - by Aidan Ryan
    We are testing our application for Unicode compatibility and have been selecting random characters outside the Latin character set for testing. On both Latin and Japanese-collated systems the following equality is true (U+3422): N'????' = N'???' but the following is not (U+30C1): N'????' = N'???' This was discovered when a test case using the first example (using U+3422) violated a unique index. Do we need to be more selective about the characters we use for testing? Obviously we don't know the semantic meaning of the above comparisons. Would this behavior be obvious to a native speaker?

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  • April 14th Links: ASP.NET, ASP.NET MVC, ASP.NET Web API and Visual Studio

    - by ScottGu
    Here is the latest in my link-listing blog series: ASP.NET Easily overlooked features in VS 11 Express for Web: Good post by Scott Hanselman that highlights a bunch of easily overlooked improvements that are coming to VS 11 (and specifically the free express editions) for web development: unit testing, browser chooser/launcher, IIS Express, CSS Color Picker, Image Preview in Solution Explorer and more. Get Started with ASP.NET 4.5 Web Forms: Good 5-part tutorial that walks-through building an application using ASP.NET Web Forms and highlights some of the nice improvements coming with ASP.NET 4.5. What is New in Razor V2 and What Else is New in Razor V2: Great posts by Andrew Nurse, a dev on the ASP.NET team, about some of the new improvements coming with ASP.NET Razor v2. ASP.NET MVC 4 AllowAnonymous Attribute: Nice post from David Hayden that talks about the new [AllowAnonymous] filter introduced with ASP.NET MVC 4. Introduction to the ASP.NET Web API: Great tutorial by Stephen Walher that covers how to use the new ASP.NET Web API support built-into ASP.NET 4.5 and ASP.NET MVC 4. Comprehensive List of ASP.NET Web API Tutorials and Articles: Tugberk Ugurlu links to a huge collection of articles, tutorials, and samples about the new ASP.NET Web API capability. Async Mashups using ASP.NET Web API: Nice post by Henrik on how you can use the new async language support coming with .NET 4.5 to easily and efficiently make asynchronous network requests that do not block threads within ASP.NET. ASP.NET and Front-End Web Development Visual Studio 11 and Front End Web Development - JavaScript/HTML5/CSS3: Nice post by Scott Hanselman that highlights some of the great improvements coming with VS 11 (including the free express edition) for front-end web development. HTML5 Drag/Drop and Async Multi-file Upload with ASP.NET Web API: Great post by Filip W. that demonstrates how to implement an async file drag/drop uploader using HTML5 and ASP.NET Web API. Device Emulator Guide for Mobile Development with ASP.NET: Good post from Rachel Appel that covers how to use various device emulators with ASP.NET and VS to develop cross platform mobile sites. Fixing these jQuery: A Guide to Debugging: Great presentation by Adam Sontag on debugging with JavaScript and jQuery.  Some really good tips, tricks and gotchas that can save a lot of time. ASP.NET and Open Source Getting Started with ASP.NET Web Stack Source on CodePlex: Fantastic post by Henrik (an architect on the ASP.NET team) that provides step by step instructions on how to work with the ASP.NET source code we recently open sourced. Contributing to ASP.NET Web Stack Source on CodePlex: Follow-on to the post above (also by Henrik) that walks-through how you can submit a code contribution to the ASP.NET MVC, Web API and Razor projects. Overview of the WebApiContrib project: Nice post by Pedro Reys on the new open source WebApiContrib project that has been started to deliver cool extensions and libraries for use with ASP.NET Web API. Entity Framework Entity Framework 5 Performance Improvements and Performance Considerations for EF5:  Good articles that describes some of the big performance wins coming with EF5 (which will ship with both .NET 4.5 and ASP.NET MVC 4). Automatic compilation of LINQ queries will yield some significant performance wins (up to 600% faster). ASP.NET MVC 4 and EF Database Migrations: Good post by David Hayden that covers the new database migrations support within EF 4.3 which allows you to easily update your database schema during development - without losing any of the data within it. Visual Studio What's New in Visual Studio 11 Unit Testing: Nice post by Peter Provost (from the VS team) that talks about some of the great improvements coming to VS11 for unit testing - including built-in VS tooling support for a broad set of unit test frameworks (including NUnit, XUnit, Jasmine, QUnit and more) Hope this helps, Scott

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  • SharpDX: best practice for multiple RenderForms?

    - by Rob Jellinghaus
    I have an XNA app, but I really need to add multiple render windows, which XNA doesn't do. I'm looking at SharpDX (both for multi-window support and for DX11 / Metro / many other reasons). I decided to hack up the SharpDX DX11 MultiCubeTexture sample to see if I could make it work. My changes are pretty trivial. The original sample had: [STAThread] private static void Main() { var form = new RenderForm("SharpDX - MiniCubeTexture Direct3D11 Sample"); ... I changed this to: struct RenderFormWithActions { internal readonly RenderForm Form; // should just be Action but it's not in System namespace?! internal readonly Action RenderAction; internal readonly Action DisposeAction; internal RenderFormWithActions(RenderForm form, Action renderAction, Action disposeAction) { Form = form; RenderAction = renderAction; DisposeAction = disposeAction; } } [STAThread] private static void Main() { // hackity hack new Thread(new ThreadStart(() = { RenderFormWithActions form1 = CreateRenderForm(); RenderLoop.Run(form1.Form, () = form1.RenderAction(0)); form1.DisposeAction(0); })).Start(); new Thread(new ThreadStart(() = { RenderFormWithActions form2 = CreateRenderForm(); RenderLoop.Run(form2.Form, () = form2.RenderAction(0)); form2.DisposeAction(0); })).Start(); } private static RenderFormWithActions CreateRenderForm() { var form = new RenderForm("SharpDX - MiniCubeTexture Direct3D11 Sample"); ... Basically, I split out all the Main() code into a separate method which creates a RenderForm and two delegates (a render delegate, and a dispose delegate), and bundles them all together into a struct. I call this method twice, each time from a separate, new thread. Then I just have one RenderLoop on each new thread. I was thinking this wouldn't work because of the [STAThread] declaration -- I thought I would need to create the RenderForm on the main (STA) thread, and run only a single RenderLoop on that thread. Fortunately, it seems I was wrong. This works quite well -- if you drag one of the forms around, it stops rendering while being dragged, but starts again when you drop it; and the other form keeps chugging away. My questions are pretty basic: Is this a reasonable approach, or is there some lurking threading issue that might make trouble? My code simply duplicates all the setup code -- it makes a duplicate SwapChain, Device, Texture2D, vertex buffer, everything. I don't have a problem with this level of duplication -- my app is not intensive enough to suffer resource issues -- but nonetheless, is there a better practice? Is there any good reference for which DirectX structures can safely be shared, and which can't? It appears that RenderLoop.Run calls the render delegate in a tight loop. Is there any standard way to limit the frame rate of RenderLoop.Run, if you don't want a 400FPS app eating 100% of your CPU? Should I just Thread.Sleep(30) in the render delegate? (I asked on the sharpdx.org forums as well, but Alexandre is on vacation for two weeks, and my sister wants me to do a performance with my app at her wedding in three and a half weeks, so I'm mighty incented here! http://robjsoftware.org for details of what I'm building....)

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  • SQL SERVER – World Shapefile Download and Upload to Database – Spatial Database

    - by pinaldave
    During my recent, training I was asked by a student if I know a place where he can download spatial files for all the countries around the world, as well as if there is a way to upload shape files to a database. Here is a quick tutorial for it. VDS Technologies has all the spatial files for every location for free. You can download the spatial file from here. If you cannot find the spatial file you are looking for, please leave a comment here, and I will send you the necessary details. Unzip the file to a folder and it will have the following content. Then, download Shape2SQL tool from SharpGIS. This is one of the best tools available to convert shapefiles to SQL tables. Afterwards, run the .exe file. When the file is run for the first time, it will ask for the database properties. Provide your database details. Select the appropriate shape files and the tool will fill up the essential details automatically. If you do not want to create the index on the column, uncheck the box beside it. The screenshot below is simply explains the procedure. You also have to be careful regarding your data, whether that is GEOMETRY or GEOGRAPHY. In this example,  it is GEOMETRY data. Click “Upload to Database”. It will show you the uploading process. Once the shape file is uploaded, close the application and open SQL Server Management Studio (SSMS). Run the following code in SSMS Query Editor. USE Spatial GO SELECT * FROM dbo.world GO This will show the complete map of world after you click on Spatial Results in Spatial Tab. In Spatial Results Set, the Zoom feature is available. From the Select label column, choose the country name in order to show the country name overlaying the country borders. Let me know if this tutorial is helpful enough. I am planning to write a few more posts about this later. Note: Please note that the images displayed here do not reflect the original political boundaries. These data are pretty old and can probably draw incorrect maps as well. I have personally spotted several parts of the map where some countries are located a little bit inaccurately. Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Add-On, SQL Authority, SQL Query, SQL Scripts, SQL Server, SQL Spatial, SQL Tips and Tricks, SQL Utility, T SQL, Technology

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  • Install usblib package - Ubuntu

    - by Tom celic
    I need the package libusb for another package I am installing. I tried the following which seemed to install the package, sudo apt-get install libusb-dev but when I try to install the other package I get, configure: error: Package requirements (libusb-1.0 >= 0.9.1) were not met: No package 'libusb-1.0' found Consider adjusting the PKG_CONFIG_PATH environment variable if you installed software in a non-standard prefix. Alternatively, you may set the environment variables LIBUSB_CFLAGS and LIBUSB_LIBS to avoid the need to call pkg-config. See the pkg-config man page for more details. When I run the command dpkg -L libusb-dev, I get: /. /usr /usr/bin /usr/bin/libusb-config /usr/include /usr/include/usb.h /usr/lib /usr/lib/libusb.a /usr/lib/libusb.la /usr/lib/pkgconfig /usr/lib/pkgconfig/libusb.pc /usr/share /usr/share/doc /usr/share/doc/libusb-dev /usr/share/doc/libusb-dev/html /usr/share/doc/libusb-dev/html/index.html /usr/share/doc/libusb-dev/html/preface.html /usr/share/doc/libusb-dev/html/intro.html /usr/share/doc/libusb-dev/html/intro-overview.html /usr/share/doc/libusb-dev/html/intro-support.html /usr/share/doc/libusb-dev/html/api.html /usr/share/doc/libusb-dev/html/api-device-interfaces.html /usr/share/doc/libusb-dev/html/api-timeouts.html /usr/share/doc/libusb-dev/html/api-types.html /usr/share/doc/libusb-dev/html/api-synchronous.html /usr/share/doc/libusb-dev/html/api-return-values.html /usr/share/doc/libusb-dev/html/functions.html /usr/share/doc/libusb-dev/html/ref.core.html /usr/share/doc/libusb-dev/html/function.usbinit.html /usr/share/doc/libusb-dev/html/function.usbfindbusses.html /usr/share/doc/libusb-dev/html/function.usbfinddevices.html /usr/share/doc/libusb-dev/html/function.usbgetbusses.html /usr/share/doc/libusb-dev/html/ref.deviceops.html /usr/share/doc/libusb-dev/html/function.usbopen.html /usr/share/doc/libusb-dev/html/function.usbclose.html /usr/share/doc/libusb-dev/html/function.usbsetconfiguration.html /usr/share/doc/libusb-dev/html/function.usbsetaltinterface.html /usr/share/doc/libusb-dev/html/function.usbresetep.html /usr/share/doc/libusb-dev/html/function.usbclearhalt.html /usr/share/doc/libusb-dev/html/function.usbreset.html /usr/share/doc/libusb-dev/html/function.usbclaiminterface.html /usr/share/doc/libusb-dev/html/function.usbreleaseinterface.html /usr/share/doc/libusb-dev/html/ref.control.html /usr/share/doc/libusb-dev/html/function.usbcontrolmsg.html /usr/share/doc/libusb-dev/html/function.usbgetstring.html /usr/share/doc/libusb-dev/html/function.usbgetstringsimple.html /usr/share/doc/libusb-dev/html/function.usbgetdescriptor.html /usr/share/doc/libusb-dev/html/function.usbgetdescriptorbyendpoint.html /usr/share/doc/libusb-dev/html/ref.bulk.html /usr/share/doc/libusb-dev/html/function.usbbulkwrite.html /usr/share/doc/libusb-dev/html/function.usbbulkread.html /usr/share/doc/libusb-dev/html/ref.interrupt.html /usr/share/doc/libusb-dev/html/function.usbinterruptwrite.html /usr/share/doc/libusb-dev/html/function.usbinterruptread.html /usr/share/doc/libusb-dev/html/ref.nonportable.html /usr/share/doc/libusb-dev/html/function.usbgetdrivernp.html /usr/share/doc/libusb-dev/html/function.usbdetachkerneldrivernp.html /usr/share/doc/libusb-dev/html/examples.html /usr/share/doc/libusb-dev/html/examples-code.html /usr/share/doc/libusb-dev/html/examples-tests.html /usr/share/doc/libusb-dev/html/examples-other.html /usr/share/doc/libusb-dev/copyright /usr/share/doc-base /usr/share/doc-base/libusb-dev /usr/share/man /usr/share/man/man1 /usr/share/man/man1/libusb-config.1.gz /usr/lib/libusb.so /usr/share/doc/libusb-dev/changelog.Debian.gz Any ideas??

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  • Windows Azure Learning Plan - Security

    - by BuckWoody
    This is one in a series of posts on a Windows Azure Learning Plan. You can find the main post here. This one deals with Security for  Windows Azure.   General Security Information Overview and general  information about Windows Azure Security - what it is, how it works, and where you can learn more. General Security Whitepaper – answers most questions http://blogs.msdn.com/b/usisvde/archive/2010/08/10/security-white-paper-on-windows-azure-answers-many-faq.aspx Windows Azure Security Notes from the Patterns and Practices site http://blogs.msdn.com/b/jmeier/archive/2010/08/03/now-available-azure-security-notes-pdf.aspx Overview of Azure Security http://www.windowsecurity.com/articles/Microsoft-Azure-Security-Cloud.html Azure Security Resources http://reddevnews.com/articles/2010/08/19/microsoft-releases-windows-azure-security-resources.aspx Cloud Computing Security Considerations http://www.microsoft.com/downloads/en/details.aspx?FamilyID=68fedf9c-1c27-4642-aa5b-0a34472303ea&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+MicrosoftDownloadCenter+%28Microsoft+Download+Center Security in Cloud Computing – a Microsoft Perspective http://www.microsoft.com/downloads/en/details.aspx?FamilyID=7c8507e8-50ca-4693-aa5a-34b7c24f4579&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+MicrosoftDownloadCenter+%28Microsoft+Download+Center Physical Security for Microsoft’s Online Computing Information on the Infrastructure and Locations for Azure Physical Security. The Global Foundation Services Group at Microsoft handles physical security http://www.globalfoundationservices.com/security/index.html Microsoft’s Security Response Center http://www.microsoft.com/security/msrc/ Software Security for Microsoft’s Online Computing Steps we take as a company to develop secure software Windows Azure is developed using the Trustworthy Computing Initiative http://www.microsoft.com/about/twc/en/us/default.aspx and  http://msdn.microsoft.com/en-us/library/ms995349.aspx Identity and Access in the Cloud http://blogs.msdn.com/b/technology_titbits_by_rajesh_makhija/archive/2010/10/29/identity-and-access-in-the-cloud.aspx Security Steps you should take While Microsoft takes great pains to secure the infrastructure, platform and code for Windows Azure, you have a responsibility to write secure code. These pointers can help you do that. Securing your cloud architecture, step-by-step http://technet.microsoft.com/en-us/magazine/gg296364.aspx Security Guidelines for Windows Azure http://redmondmag.com/articles/2010/06/15/microsoft-issues-security-guidelines-for-windows-azure.aspx  Best Practices for Windows Azure Security http://blogs.msdn.com/b/vbertocci/archive/2010/06/14/security-best-practices-for-developing-windows-azure-applications.aspx Active Directory and Windows Azure http://blogs.msdn.com/b/plankytronixx/archive/2010/10/22/projecting-your-active-directory-identity-to-the-azure-cloud.aspx Understanding Encryption (great overview and tutorial) http://blogs.msdn.com/b/plankytronixx/archive/2010/10/23/crypto-primer-understanding-encryption-public-private-key-signatures-and-certificates.aspx Securing your Connection Strings (SQL Azure) http://blogs.msdn.com/b/sqlazure/archive/2010/09/07/10058942.aspx Getting started with Windows Identity Foundation (WIF) quickly http://blogs.msdn.com/b/alikl/archive/2010/10/26/windows-identity-foundation-wif-fast-track.aspx

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  • TestDriven.Net 3.0 – All Systems Go

    - by Jamie Cansdale
    I’m pleased to announce that TestDriven.Net 3.0 is now available. Finally! I know many of you will already be using the Beta and RC versions, but if you look at the release notes you’ll see there’s been many refinements since then, so I highly recommend you install the RTM version. Here is a quick summary of a few new features: Visual Studio 2010 supports targeting multiple versions of the .NET framework (multi-targeting). This means you can easily upgrade your Visual Studio 2005/2008 solutions without necessarily converting them to use .NET 4.0. TestDriven.Net will execute your tests using the .NET version your test project is targeting (see ‘Properties > Application > Target framework’). There is now first class support for MSTest when using Visual Studio 2008 & 2010. Previous versions of TestDriven.Net had support for a limited number of MSTest attributes. This version supports virtually all MSTest unit testing related attributes, including support for deployment item and data driven test attributes. You should also find this test runner is quick. ;) There is a new ‘Go To Test/Code’ command on the code context menu. You can think of this as Ctrl-Tab for test driven developers; it will quickly flip back and forth between your tests and code under test. I recommend assigning a keyboard shortcut to the ‘TestDriven.NET.GoToTestOrCode’ command. NCover can now be used for code coverage on .NET 4.0. This is only officially supported since NCover 3.2 (your mileage may vary if you’re using the 1.5.8 version). Rather than clutter the ‘Output’ window, ignored or skipped tests will be placed on the ‘Task List’. You can double-click on these items to navigate to the offending test (or assign a keyboard shortcut to ‘View.NextTask’). If you’re using a Team, Premium or Ultimate edition of Visual Studio 2005-2010, a new ‘Test With > Performance’ command will be available. This command will perform instrumented performance profiling on your target code. A particular focus of this version has been to make it more keyboard friendly. Here’s a list of commands you will probably want to assign keyboard shortcuts to: Name Default What I use TestDriven.NET.RunTests Run tests in context   Alt + T TestDriven.NET.RerunTests Repeat test run   Alt + R TestDriven.NET.GoToTestOrCode Flip between tests and code   Alt + G TestDriven.NET.Debugger Run tests with debugger   Alt + D View.Output Show the ‘Output’ window Ctrl+ Alt + O   Edit.BreakLine Edit code in stack trace Enter   View.NextError Jump to next failed test Ctrl + Shift + F12   View.NextTask Jump to next skipped test   Alt + S   By default the ‘Output’ window will automatically activate when there is test output or a failed test (this is an option). The cursor will be positioned on the stack trace of the last failed test, ready for you to hit ‘Enter’ to jump to the fail point or ‘Esc’ to return to your source (assuming your ‘Output’ window is set to auto-hide).  If your ‘Output’ window isn’t set to auto-hide, you’ll need to hit ‘Ctrl + Alt + O’ then ‘Enter’. Alternatively you can use ‘Ctrl + Shift + F12’ (View.NextError) to navigate between all failed tests.   For more frequent updates or to give feedback, you can find me on twitter here. I hope you enjoy this version. Let me know how you get on. :)

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  • Tom Kyte Budapestre jön!

    - by Lajos Sárecz
    Épp azon tunodöm, hogy blogom olvasói között van-e olyan, aki ne ismerné a asktom.oracle.com oldalt. Gyanítom, hogy kevesen vannak. Bár Tom mostanában elég elfoglaltnak tunik, hiszen népszeru oldalán jelenleg azt kéri, hogy elmaradásai miatt késobb kérdezzenek tole, most csupán a már megválaszolt kérdések böngészésére van lehetoség. Megjegyzem ez sem kis ajándék, ráadásul a mester aktivitását mutatja az az adat, amely a fooldalon látható: Az elmúlt négy hétben 47 új kérdést kapott, elolvasott 532 reakciót és megválaszolt ezek közül 380-at. Csoda, hogy van ideje átruccanni Európába, és eloadást tartani a hazai szakembereknek is. Információim szerint ez olyannyira egyedülálló lehetoség lesz, hogy eddig még ilyen nem volt Magyarországon, másrészt valószínuleg a jövoben nem is nagyon lesz még a régióban sem, mivel egyre inkább az a trend hogy úgynevezett virtual class-okat fog tartani o is, azaz személyesen majd maximum az éves OpenWorld konferencián lehet ot látni egy-egy eloadás erejéig. Áprilisban, Budapesten viszont két teljes napig lehet hallgatni tole a hasznosabbnál hasznosabb tanácsokat. Mik is lesznek ezek? Miért fontos a bind változók használata? Hogyan segíti a teljesítményt, a skálázhatóságot és még a biztonságot is? Hogyan muködik a materializált nézet? Mikor érdemes használni és hogyan lehet a leghasznosabbá tenni? Mikor milyen indexet érdemes használni? Mindenki tisztában van azzal, hogy indexekre szükség van, az már kevésbé egyértelmu mikor melyiket érdemes használni az optimális teljesítmény érdekében. Az eloadáson választ kapunk arra is Tom Kyte-tól, milyen szempontok alapján kell kiválasztani a megfelelo indexelést. Milyen adattárolási formákat érdemes választani? Elsore tán nem is gondolnánk hányféle trükk van az adatok optimális tárolására. Hogy csak a legfontosabbakat említsem: klaszeterezett adatszervezés, index-szervezésu tábla, particionálás, tömörítés. Mikor van szükség az adatok átszervezésére? Mik a legjobb technikák az adatok átszervezésére, hogyan lehet ezt úgy végrehajtani, hogy legkevésbé érintse az alkalmazás felhasználóit? Azt gondolom ezek a témák minden gyakorló rendszergazdának és Oracle fejlesztonek ismerosen csengenek, azonban abban egészen biztos vagyok, hogy mindenki számos újdonságot, hasznos tanácsot kaphat, ha részt vesz Thomas Kyte 2 napos tréningjén. Ja és nem utolsó sorban, egészen biztos, hogy lehetoség lesz kérdezni is Tom-tól! További információ és a regisztráció az Oracle University oldalán érheto el.

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  • Top 31 Favorite Features in Windows Server 2012

    - by KeithMayer
    Over the past month, my fellow IT Pro Technical Evangelists and I have authored a series of articles about our Top 31 Favorite Features in Windows Server 2012.  Now that our series is complete, I’m providing a clickable index below of all of the articles in the series for your convenience, just in case you perhaps missed any of them when they were first released.  Hope you enjoy our Favorite Features in Windows Server 2012! Top 31 Favorite Features in Windows Server 2012 The Cloud OS Platform by Kevin Remde Server Manager in Windows Server 2012 by Brian Lewis Feel the Power of PowerShell 3.0 by Matt Hester Live Migrate Your VMS in One Line of PowerShell by Keith Mayer Windows Server 2012 and Hyper-V Replica by Kevin Remde Right-size IT Budgets with “Storage Spaces” by Keith Mayer Yes, there is an “I” in Team – the NIC Team! by Kevin Remde Hyper-V Network Virtualization by Keith Mayer Get Happy over the FREE Hyper-V Server 2012 by Matt Hester Simplified BranchCache in Windows Server 2012 by Brian Lewis Getting Snippy with PowerShell 3.0 by Matt Hester How to Get Unbelievable Data Deduplication Results by Chris Henley of Veeam Simplified VDI Configuration and Management by Brian Lewis Taming the New Task Manager by Keith Mayer Improve File Server Resiliency with ReFS by Keith Mayer Simplified DirectAccess by Sumeeth Evans SMB 3.0 – The Glue in Windows Server 2012 by Matt Hester Continuously Available File Shares by Steven Murawski of Edgenet Server Core - Improved Taste, Less Filling, More Uptime by Keith Mayer Extend Your Hyper-V Virtual Switch by Kevin Remde To NIC or to Not NIC Hardware Requirements by Brian Lewis Simplified Licensing and Server Versions by Kevin Remde I Think, Therefore IPAM! by Kevin Remde Windows Server 2012 and the RSATs by Kevin Remde Top 3 New Tricks in the Active Directory Admin Center by Keith Mayer Dynamic Access Control by Brian Lewis Get the Gremlin out of Your Active Directory Virtualized Infrastructure by Matt Hester Scoping out the New DHCP Failover by Keith Mayer Gone in 8 Seconds – The New CHKDSK by Matt Hester New Remote Desktop Services (RDS) by Brian Lewis No Better Time Than Now to Choose Hyper-V by Matt Hester What’s Next? Keep Learning! Want to learn more about Windows Server 2012 and Hyper-V Server 2012?  Want to prepare for certification on Windows Server 2012? Do It: Join our Windows Server 2012 “Early Experts” Challenge online peer study group for FREE at http://earlyexperts.net. You’ll get FREE access to video-based lectures, structured study materials and hands-on lab activities to help you study and prepare!  Along the way, you’ll be part of an IT Pro community of over 1,000+ IT Pros that are all helping each other learn Windows Server 2012! What are Your Favorite Features? Do you have a Favorite Feature in Windows Server 2012 that we missed in our list above?  Feel free to share your favorites in the comments below! Keith Build Your Lab! Download Windows Server 2012 Don’t Have a Lab? Build Your Lab in the Cloud with Windows Azure Virtual Machines Want to Get Certified? Join our Windows Server 2012 "Early Experts" Study Group

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  • Oracle Announces Oracle Exadata X3 Database In-Memory Machine

    - by jgelhaus
    Fourth Generation Exadata X3 Systems are Ideal for High-End OLTP, Large Data Warehouses, and Database Clouds; Eighth-Rack Configuration Offers New Low-Cost Entry Point ORACLE OPENWORLD, SAN FRANCISCO – October 1, 2012 News Facts During his opening keynote address at Oracle OpenWorld, Oracle CEO, Larry Ellison announced the Oracle Exadata X3 Database In-Memory Machine - the latest generation of its Oracle Exadata Database Machines. The Oracle Exadata X3 Database In-Memory Machine is a key component of the Oracle Cloud. Oracle Exadata X3-2 Database In-Memory Machine and Oracle Exadata X3-8 Database In-Memory Machine can store up to hundreds of Terabytes of compressed user data in Flash and RAM memory, virtually eliminating the performance overhead of reads and writes to slow disk drives, making Exadata X3 systems the ideal database platforms for the varied and unpredictable workloads of cloud computing. In order to realize the highest performance at the lowest cost, the Oracle Exadata X3 Database In-Memory Machine implements a mass memory hierarchy that automatically moves all active data into Flash and RAM memory, while keeping less active data on low-cost disks. With a new Eighth-Rack configuration, the Oracle Exadata X3-2 Database In-Memory Machine delivers a cost-effective entry point for smaller workloads, testing, development and disaster recovery systems, and is a fully redundant system that can be used with mission critical applications. Next-Generation Technologies Deliver Dramatic Performance Improvements Oracle Exadata X3 Database In-Memory Machines use a combination of scale-out servers and storage, InfiniBand networking, smart storage, PCI Flash, smart memory caching, and Hybrid Columnar Compression to deliver extreme performance and availability for all Oracle Database Workloads. Oracle Exadata X3 Database In-Memory Machine systems leverage next-generation technologies to deliver significant performance enhancements, including: Four times the Flash memory capacity of the previous generation; with up to 40 percent faster response times and 100 GB/second data scan rates. Combined with Exadata’s unique Hybrid Columnar Compression capabilities, hundreds of Terabytes of user data can now be managed entirely within Flash; 20 times more capacity for database writes through updated Exadata Smart Flash Cache software. The new Exadata Smart Flash Cache software also runs on previous generation Exadata systems, increasing their capacity for writes tenfold; 33 percent more database CPU cores in the Oracle Exadata X3-2 Database In-Memory Machine, using the latest 8-core Intel® Xeon E5-2600 series of processors; Expanded 10Gb Ethernet connectivity to the data center in the Oracle Exadata X3-2 provides 40 10Gb network ports per rack for connecting users and moving data; Up to 30 percent reduction in power and cooling. Configured for Your Business, Available Today Oracle Exadata X3-2 Database In-Memory Machine systems are available in a Full-Rack, Half-Rack, Quarter-Rack, and the new low-cost Eighth-Rack configuration to satisfy the widest range of applications. Oracle Exadata X3-8 Database In-Memory Machine systems are available in a Full-Rack configuration, and both X3 systems enable multi-rack configurations for virtually unlimited scalability. Oracle Exadata X3-2 and X3-8 Database In-Memory Machines are fully compatible with prior Exadata generations and existing systems can also be upgraded with Oracle Exadata X3-2 servers. Oracle Exadata X3 Database In-Memory Machine systems can be used immediately with any application certified with Oracle Database 11g R2 and Oracle Real Application Clusters, including SAP, Oracle Fusion Applications, Oracle’s PeopleSoft, Oracle’s Siebel CRM, the Oracle E-Business Suite, and thousands of other applications. Supporting Quotes “Forward-looking enterprises are moving towards Cloud Computing architectures,” said Andrew Mendelsohn, senior vice president, Oracle Database Server Technologies. “Oracle Exadata’s unique ability to run any database application on a fully scale-out architecture using a combination of massive memory for extreme performance and low-cost disk for high capacity delivers the ideal solution for Cloud-based database deployments today.” Supporting Resources Oracle Press Release Oracle Exadata Database Machine Oracle Exadata X3-2 Database In-Memory Machine Oracle Exadata X3-8 Database In-Memory Machine Oracle Database 11g Follow Oracle Database via Blog, Facebook and Twitter Oracle OpenWorld 2012 Oracle OpenWorld 2012 Keynotes Like Oracle OpenWorld on Facebook Follow Oracle OpenWorld on Twitter Oracle OpenWorld Blog Oracle OpenWorld on LinkedIn Mark Hurd's keynote with Andy Mendelsohn and Juan Loaiza - - watch for the replay to be available soon at http://www.youtube.com/user/Oracle or http://www.oracle.com/openworld/live/on-demand/index.html

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  • Using Durandal to Create Single Page Apps

    - by Stephen.Walther
    A few days ago, I gave a talk on building Single Page Apps on the Microsoft Stack. In that talk, I recommended that people use Knockout, Sammy, and RequireJS to build their presentation layer and use the ASP.NET Web API to expose data from their server. After I gave the talk, several people contacted me and suggested that I investigate a new open-source JavaScript library named Durandal. Durandal stitches together Knockout, Sammy, and RequireJS to make it easier to use these technologies together. In this blog entry, I want to provide a brief walkthrough of using Durandal to create a simple Single Page App. I am going to demonstrate how you can create a simple Movies App which contains (virtual) pages for viewing a list of movies, adding new movies, and viewing movie details. The goal of this blog entry is to give you a sense of what it is like to build apps with Durandal. Installing Durandal First things first. How do you get Durandal? The GitHub project for Durandal is located here: https://github.com/BlueSpire/Durandal The Wiki — located at the GitHub project — contains all of the current documentation for Durandal. Currently, the documentation is a little sparse, but it is enough to get you started. Instead of downloading the Durandal source from GitHub, a better option for getting started with Durandal is to install one of the Durandal NuGet packages. I built the Movies App described in this blog entry by first creating a new ASP.NET MVC 4 Web Application with the Basic Template. Next, I executed the following command from the Package Manager Console: Install-Package Durandal.StarterKit As you can see from the screenshot of the Package Manager Console above, the Durandal Starter Kit package has several dependencies including: · jQuery · Knockout · Sammy · Twitter Bootstrap The Durandal Starter Kit package includes a sample Durandal application. You can get to the Starter Kit app by navigating to the Durandal controller. Unfortunately, when I first tried to run the Starter Kit app, I got an error because the Starter Kit is hard-coded to use a particular version of jQuery which is already out of date. You can fix this issue by modifying the App_Start\DurandalBundleConfig.cs file so it is jQuery version agnostic like this: bundles.Add( new ScriptBundle("~/scripts/vendor") .Include("~/Scripts/jquery-{version}.js") .Include("~/Scripts/knockout-{version}.js") .Include("~/Scripts/sammy-{version}.js") // .Include("~/Scripts/jquery-1.9.0.min.js") // .Include("~/Scripts/knockout-2.2.1.js") // .Include("~/Scripts/sammy-0.7.4.min.js") .Include("~/Scripts/bootstrap.min.js") ); The recommendation is that you create a Durandal app in a folder off your project root named App. The App folder in the Starter Kit contains the following subfolders and files: · durandal – This folder contains the actual durandal JavaScript library. · viewmodels – This folder contains all of your application’s view models. · views – This folder contains all of your application’s views. · main.js — This file contains all of the JavaScript startup code for your app including the client-side routing configuration. · main-built.js – This file contains an optimized version of your application. You need to build this file by using the RequireJS optimizer (unfortunately, before you can run the optimizer, you must first install NodeJS). For the purpose of this blog entry, I wanted to start from scratch when building the Movies app, so I deleted all of these files and folders except for the durandal folder which contains the durandal library. Creating the ASP.NET MVC Controller and View A Durandal app is built using a single server-side ASP.NET MVC controller and ASP.NET MVC view. A Durandal app is a Single Page App. When you navigate between pages, you are not navigating to new pages on the server. Instead, you are loading new virtual pages into the one-and-only-one server-side view. For the Movies app, I created the following ASP.NET MVC Home controller: public class HomeController : Controller { public ActionResult Index() { return View(); } } There is nothing special about the Home controller – it is as basic as it gets. Next, I created the following server-side ASP.NET view. This is the one-and-only server-side view used by the Movies app: @{ Layout = null; } <!DOCTYPE html> <html> <head> <title>Index</title> </head> <body> <div id="applicationHost"> Loading app.... </div> @Scripts.Render("~/scripts/vendor") <script type="text/javascript" src="~/App/durandal/amd/require.js" data-main="/App/main"></script> </body> </html> Notice that I set the Layout property for the view to the value null. If you neglect to do this, then the default ASP.NET MVC layout will be applied to the view and you will get the <!DOCTYPE> and opening and closing <html> tags twice. Next, notice that the view contains a DIV element with the Id applicationHost. This marks the area where virtual pages are loaded. When you navigate from page to page in a Durandal app, HTML page fragments are retrieved from the server and stuck in the applicationHost DIV element. Inside the applicationHost element, you can place any content which you want to display when a Durandal app is starting up. For example, you can create a fancy splash screen. I opted for simply displaying the text “Loading app…”: Next, notice the view above includes a call to the Scripts.Render() helper. This helper renders out all of the JavaScript files required by the Durandal library such as jQuery and Knockout. Remember to fix the App_Start\DurandalBundleConfig.cs as described above or Durandal will attempt to load an old version of jQuery and throw a JavaScript exception and stop working. Your application JavaScript code is not included in the scripts rendered by the Scripts.Render helper. Your application code is loaded dynamically by RequireJS with the help of the following SCRIPT element located at the bottom of the view: <script type="text/javascript" src="~/App/durandal/amd/require.js" data-main="/App/main"></script> The data-main attribute on the SCRIPT element causes RequireJS to load your /app/main.js JavaScript file to kick-off your Durandal app. Creating the Durandal Main.js File The Durandal Main.js JavaScript file, located in your App folder, contains all of the code required to configure the behavior of Durandal. Here’s what the Main.js file looks like in the case of the Movies app: require.config({ paths: { 'text': 'durandal/amd/text' } }); define(function (require) { var app = require('durandal/app'), viewLocator = require('durandal/viewLocator'), system = require('durandal/system'), router = require('durandal/plugins/router'); //>>excludeStart("build", true); system.debug(true); //>>excludeEnd("build"); app.start().then(function () { //Replace 'viewmodels' in the moduleId with 'views' to locate the view. //Look for partial views in a 'views' folder in the root. viewLocator.useConvention(); //configure routing router.useConvention(); router.mapNav("movies/show"); router.mapNav("movies/add"); router.mapNav("movies/details/:id"); app.adaptToDevice(); //Show the app by setting the root view model for our application with a transition. app.setRoot('viewmodels/shell', 'entrance'); }); }); There are three important things to notice about the main.js file above. First, notice that it contains a section which enables debugging which looks like this: //>>excludeStart(“build”, true); system.debug(true); //>>excludeEnd(“build”); This code enables debugging for your Durandal app which is very useful when things go wrong. When you call system.debug(true), Durandal writes out debugging information to your browser JavaScript console. For example, you can use the debugging information to diagnose issues with your client-side routes: (The funny looking //> symbols around the system.debug() call are RequireJS optimizer pragmas). The main.js file is also the place where you configure your client-side routes. In the case of the Movies app, the main.js file is used to configure routes for three page: the movies show, add, and details pages. //configure routing router.useConvention(); router.mapNav("movies/show"); router.mapNav("movies/add"); router.mapNav("movies/details/:id");   The route for movie details includes a route parameter named id. Later, we will use the id parameter to lookup and display the details for the right movie. Finally, the main.js file above contains the following line of code: //Show the app by setting the root view model for our application with a transition. app.setRoot('viewmodels/shell', 'entrance'); This line of code causes Durandal to load up a JavaScript file named shell.js and an HTML fragment named shell.html. I’ll discuss the shell in the next section. Creating the Durandal Shell You can think of the Durandal shell as the layout or master page for a Durandal app. The shell is where you put all of the content which you want to remain constant as a user navigates from virtual page to virtual page. For example, the shell is a great place to put your website logo and navigation links. The Durandal shell is composed from two parts: a JavaScript file and an HTML file. Here’s what the HTML file looks like for the Movies app: <h1>Movies App</h1> <div class="container-fluid page-host"> <!--ko compose: { model: router.activeItem, //wiring the router afterCompose: router.afterCompose, //wiring the router transition:'entrance', //use the 'entrance' transition when switching views cacheViews:true //telling composition to keep views in the dom, and reuse them (only a good idea with singleton view models) }--><!--/ko--> </div> And here is what the JavaScript file looks like: define(function (require) { var router = require('durandal/plugins/router'); return { router: router, activate: function () { return router.activate('movies/show'); } }; }); The JavaScript file contains the view model for the shell. This view model returns the Durandal router so you can access the list of configured routes from your shell. Notice that the JavaScript file includes a function named activate(). This function loads the movies/show page as the first page in the Movies app. If you want to create a different default Durandal page, then pass the name of a different age to the router.activate() method. Creating the Movies Show Page Durandal pages are created out of a view model and a view. The view model contains all of the data and view logic required for the view. The view contains all of the HTML markup for rendering the view model. Let’s start with the movies show page. The movies show page displays a list of movies. The view model for the show page looks like this: define(function (require) { var moviesRepository = require("repositories/moviesRepository"); return { movies: ko.observable(), activate: function() { this.movies(moviesRepository.listMovies()); } }; }); You create a view model by defining a new RequireJS module (see http://requirejs.org). You create a RequireJS module by placing all of your JavaScript code into an anonymous function passed to the RequireJS define() method. A RequireJS module has two parts. You retrieve all of the modules which your module requires at the top of your module. The code above depends on another RequireJS module named repositories/moviesRepository. Next, you return the implementation of your module. The code above returns a JavaScript object which contains a property named movies and a method named activate. The activate() method is a magic method which Durandal calls whenever it activates your view model. Your view model is activated whenever you navigate to a page which uses it. In the code above, the activate() method is used to get the list of movies from the movies repository and assign the list to the view model movies property. The HTML for the movies show page looks like this: <table> <thead> <tr> <th>Title</th><th>Director</th> </tr> </thead> <tbody data-bind="foreach:movies"> <tr> <td data-bind="text:title"></td> <td data-bind="text:director"></td> <td><a data-bind="attr:{href:'#/movies/details/'+id}">Details</a></td> </tr> </tbody> </table> <a href="#/movies/add">Add Movie</a> Notice that this is an HTML fragment. This fragment will be stuffed into the page-host DIV element in the shell.html file which is stuffed, in turn, into the applicationHost DIV element in the server-side MVC view. The HTML markup above contains data-bind attributes used by Knockout to display the list of movies (To learn more about Knockout, visit http://knockoutjs.com). The list of movies from the view model is displayed in an HTML table. Notice that the page includes a link to a page for adding a new movie. The link uses the following URL which starts with a hash: #/movies/add. Because the link starts with a hash, clicking the link does not cause a request back to the server. Instead, you navigate to the movies/add page virtually. Creating the Movies Add Page The movies add page also consists of a view model and view. The add page enables you to add a new movie to the movie database. Here’s the view model for the add page: define(function (require) { var app = require('durandal/app'); var router = require('durandal/plugins/router'); var moviesRepository = require("repositories/moviesRepository"); return { movieToAdd: { title: ko.observable(), director: ko.observable() }, activate: function () { this.movieToAdd.title(""); this.movieToAdd.director(""); this._movieAdded = false; }, canDeactivate: function () { if (this._movieAdded == false) { return app.showMessage('Are you sure you want to leave this page?', 'Navigate', ['Yes', 'No']); } else { return true; } }, addMovie: function () { // Add movie to db moviesRepository.addMovie(ko.toJS(this.movieToAdd)); // flag new movie this._movieAdded = true; // return to list of movies router.navigateTo("#/movies/show"); } }; }); The view model contains one property named movieToAdd which is bound to the add movie form. The view model also has the following three methods: 1. activate() – This method is called by Durandal when you navigate to the add movie page. The activate() method resets the add movie form by clearing out the movie title and director properties. 2. canDeactivate() – This method is called by Durandal when you attempt to navigate away from the add movie page. If you return false then navigation is cancelled. 3. addMovie() – This method executes when the add movie form is submitted. This code adds the new movie to the movie repository. I really like the Durandal canDeactivate() method. In the code above, I use the canDeactivate() method to show a warning to a user if they navigate away from the add movie page – either by clicking the Cancel button or by hitting the browser back button – before submitting the add movie form: The view for the add movie page looks like this: <form data-bind="submit:addMovie"> <fieldset> <legend>Add Movie</legend> <div> <label> Title: <input data-bind="value:movieToAdd.title" required /> </label> </div> <div> <label> Director: <input data-bind="value:movieToAdd.director" required /> </label> </div> <div> <input type="submit" value="Add" /> <a href="#/movies/show">Cancel</a> </div> </fieldset> </form> I am using Knockout to bind the movieToAdd property from the view model to the INPUT elements of the HTML form. Notice that the FORM element includes a data-bind attribute which invokes the addMovie() method from the view model when the HTML form is submitted. Creating the Movies Details Page You navigate to the movies details Page by clicking the Details link which appears next to each movie in the movies show page: The Details links pass the movie ids to the details page: #/movies/details/0 #/movies/details/1 #/movies/details/2 Here’s what the view model for the movies details page looks like: define(function (require) { var router = require('durandal/plugins/router'); var moviesRepository = require("repositories/moviesRepository"); return { movieToShow: { title: ko.observable(), director: ko.observable() }, activate: function (context) { // Grab movie from repository var movie = moviesRepository.getMovie(context.id); // Add to view model this.movieToShow.title(movie.title); this.movieToShow.director(movie.director); } }; }); Notice that the view model activate() method accepts a parameter named context. You can take advantage of the context parameter to retrieve route parameters such as the movie Id. In the code above, the context.id property is used to retrieve the correct movie from the movie repository and the movie is assigned to a property named movieToShow exposed by the view model. The movie details view displays the movieToShow property by taking advantage of Knockout bindings: <div> <h2 data-bind="text:movieToShow.title"></h2> directed by <span data-bind="text:movieToShow.director"></span> </div> Summary The goal of this blog entry was to walkthrough building a simple Single Page App using Durandal and to get a feel for what it is like to use this library. I really like how Durandal stitches together Knockout, Sammy, and RequireJS and establishes patterns for using these libraries to build Single Page Apps. Having a standard pattern which developers on a team can use to build new pages is super valuable. Once you get the hang of it, using Durandal to create new virtual pages is dead simple. Just define a new route, view model, and view and you are done. I also appreciate the fact that Durandal did not attempt to re-invent the wheel and that Durandal leverages existing JavaScript libraries such as Knockout, RequireJS, and Sammy. These existing libraries are powerful libraries and I have already invested a considerable amount of time in learning how to use them. Durandal makes it easier to use these libraries together without losing any of their power. Durandal has some additional interesting features which I have not had a chance to play with yet. For example, you can use the RequireJS optimizer to combine and minify all of a Durandal app’s code. Also, Durandal supports a way to create custom widgets (client-side controls) by composing widgets from a controller and view. You can download the code for the Movies app by clicking the following link (this is a Visual Studio 2012 project): Durandal Movie App

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  • Sneak peek at next generation Three MiFi unit – Huawei E585

    - by Liam Westley
    Last Wednesday I was fortunate to be invited to a sneak preview of the next generation Three MiFi unit, the Huawei E585. Many thanks to all those who posted questions both via this blog or via @westleyl on Twitter. I think I made sure I asked every question posed to the MiFi product manager from Three UK, and so here's the answers you were after. What is a MiFi? For those who are wondering, a MiFi unit is a 3G broadband modem combined with a WiFi access point, providing 3G broadband data access to up to five devices simultaneously via standard WiFi connections. What is different? It appears the prime task of enhancing the MiFi was to improve the user experience and user interface, both in terms of the device hardware and within the management software to configure the device.  I think this was a very sensible decision as these areas had substantial room for improvement. Single button operation to switch on, enable WiFi and connect to 3G Improved OELD display (see below), replacing the multi coloured LEDs; including signal strength, SMS notifications, the number of connected clients and data usage Management is via a web based dashboard accessible from any web browser. This is a big win for those running Linux, Mac OS/X, iPad users and, for me, as I can now configure the device from Windows 7 64-bit Charging is via micro USB, the new standard for small USB devices; you cannot use your old charger for the new MiFi unit Automatic reconnection when regaining a signal Improved charging time, which should allow recharging of the device when in use Although subjective, the black and silver design does look more classy than the silver and white plastic of the original MiFi What is the same? Virtually the same size and weight The battery is the same unit as the original MiFi so you’ll have a handy spare if you upgrade Data plans remain the same as the current MiFi, so cheapest price for upgraders will be £49 pay as you go Still only works on 3G networks, with no fallback to GPRS or EDGE There is no specific upgrade path for existing three customers, either from dongle or from the original MiFi My opinion I think three have concentrated on the correct areas of usability and user experience rather than trying to add new whizz bang technology features which aren’t of interest to mainstream users. The one button operation and the improved device display will make it much easier to use when out and about. If the automatic reconnection proves reliable that will remove a major bugbear that I experienced the previous evening when travelling on the First Great Western line from Paddington to Didcot Parkway.  The signal was repeatedly lost as we sped through tunnels and cuttings, and without automatic reconnection is was a real pain to keep pressing the data button on the MiFi to re-establish my data connection. And finally, the web based dashboard will mean I no longer need to resort to my XP based netbook to configure the SSID and password. My everyday laptop runs Windows 7 64-bit which appears to confuse the older 3 WiFi manager which cannot locate the MiFi when connected. Links to other sites, and other images of the device Good first impressions from Ben Smith, http://thereallymobileproject.com/2010/06/3uk-announce-a-new-mifi-with-a-screen/ Also, a round up of other sneak preview posts, http://www.3mobilebuzz.com/2010/06/11/mifi-round-two-your-view/ Pictures Here is a comparison of the old MiFi device next to the new device, complete with OLED display and the Huawei logo now being a prominent feature on the front of the device. One of my fellow bloggers had a Linux based netbook, showing off the web based dashboard complete with Text messages panel to manage SMS. And finally, I never thought that my blog sub title would ever end up printed onto a cup cake, ... and here's some of the other cup cakes ...

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  • A Taxonomy of Numerical Methods v1

    - by JoshReuben
    Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms     Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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  • Entity Framework Code-First, OData & Windows Phone Client

    - by Jon Galloway
    Entity Framework Code-First is the coolest thing since sliced bread, Windows  Phone is the hottest thing since Tickle-Me-Elmo and OData is just too great to ignore. As part of the Full Stack project, we wanted to put them together, which turns out to be pretty easy… once you know how.   EF Code-First CTP5 is available now and there should be very few breaking changes in the release edition, which is due early in 2011.  Note: EF Code-First evolved rapidly and many of the existing documents and blog posts which were written with earlier versions, may now be obsolete or at least misleading.   Code-First? With traditional Entity Framework you start with a database and from that you generate “entities” – classes that bridge between the relational database and your object oriented program. With Code-First (Magic-Unicorn) (see Hanselman’s write up and this later write up by Scott Guthrie) the Entity Framework looks at classes you created and says “if I had created these classes, the database would have to have looked like this…” and creates the database for you! By deriving your entity collections from DbSet and exposing them via a class that derives from DbContext, you "turn on" database backing for your POCO with a minimum of code and no hidden designer or configuration files. POCO == Plain Old CLR Objects Your entity objects can be used throughout your applications - in web applications, console applications, Silverlight and Windows Phone applications, etc. In our case, we'll want to read and update data from a Windows Phone client application, so we'll expose the entities through a DataService and hook the Windows Phone client application to that data via proxies.  Piece of Pie.  Easy as cake. The Demo Architecture To see this at work, we’ll create an ASP.NET/MVC application which will act as the host for our Data Service.  We’ll create an incredibly simple data layer using EF Code-First on top of SQLCE4 and we’ll expose the data in a WCF Data Service using the oData protocol.  Our Windows Phone 7 client will instantiate  the data context via a URI and load the data asynchronously. Setting up the Server project with MVC 3, EF Code First, and SQL CE 4 Create a new application of type ASP.NET MVC 3 and name it DeadSimpleServer.  We need to add the latest SQLCE4 and Entity Framework Code First CTP's to our project. Fortunately, NuGet makes that really easy. Open the Package Manager Console (View / Other Windows / Package Manager Console) and type in "Install-Package EFCodeFirst.SqlServerCompact" at the PM> command prompt. Since NuGet handles dependencies for you, you'll see that it installs everything you need to use Entity Framework Code First in your project. PM> install-package EFCodeFirst.SqlServerCompact 'SQLCE (= 4.0.8435.1)' not installed. Attempting to retrieve dependency from source... Done 'EFCodeFirst (= 0.8)' not installed. Attempting to retrieve dependency from source... Done 'WebActivator (= 1.0.0.0)' not installed. Attempting to retrieve dependency from source... Done You are downloading SQLCE from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'SQLCE 4.0.8435.1' You are downloading EFCodeFirst from Microsoft, the license agreement to which is available at http://go.microsoft.com/fwlink/?LinkID=206497. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst 0.8' Successfully installed 'WebActivator 1.0.0.0' You are downloading EFCodeFirst.SqlServerCompact from Microsoft, the license agreement to which is available at http://173.203.67.148/licenses/SQLCE/EULA_ENU.rtf. Check the package for additional dependencies, which may come with their own license agreement(s). Your use of the package and dependencies constitutes your acceptance of their license agreements. If you do not accept the license agreement(s), then delete the relevant components from your device. Successfully installed 'EFCodeFirst.SqlServerCompact 0.8' Successfully added 'SQLCE 4.0.8435.1' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst 0.8' to EfCodeFirst-CTP5 Successfully added 'WebActivator 1.0.0.0' to EfCodeFirst-CTP5 Successfully added 'EFCodeFirst.SqlServerCompact 0.8' to EfCodeFirst-CTP5 Note: We're using SQLCE 4 with Entity Framework here because they work really well together from a development scenario, but you can of course use Entity Framework Code First with other databases supported by Entity framework. Creating The Model using EF Code First Now we can create our model class. Right-click the Models folder and select Add/Class. Name the Class Person.cs and add the following code: using System.Data.Entity; namespace DeadSimpleServer.Models { public class Person { public int ID { get; set; } public string Name { get; set; } } public class PersonContext : DbContext { public DbSet<Person> People { get; set; } } } Notice that the entity class Person has no special interfaces or base class. There's nothing special needed to make it work - it's just a POCO. The context we'll use to access the entities in the application is called PersonContext, but you could name it anything you wanted. The important thing is that it inherits DbContext and contains one or more DbSet which holds our entity collections. Adding Seed Data We need some testing data to expose from our service. The simplest way to get that into our database is to modify the CreateCeDatabaseIfNotExists class in AppStart_SQLCEEntityFramework.cs by adding some seed data to the Seed method: protected virtual void Seed( TContext context ) { var personContext = context as PersonContext; personContext.People.Add( new Person { ID = 1, Name = "George Washington" } ); personContext.People.Add( new Person { ID = 2, Name = "John Adams" } ); personContext.People.Add( new Person { ID = 3, Name = "Thomas Jefferson" } ); personContext.SaveChanges(); } The CreateCeDatabaseIfNotExists class name is pretty self-explanatory - when our DbContext is accessed and the database isn't found, a new one will be created and populated with the data in the Seed method. There's one more step to make that work - we need to uncomment a line in the Start method at the top of of the AppStart_SQLCEEntityFramework class and set the context name, as shown here, public static class AppStart_SQLCEEntityFramework { public static void Start() { DbDatabase.DefaultConnectionFactory = new SqlCeConnectionFactory("System.Data.SqlServerCe.4.0"); // Sets the default database initialization code for working with Sql Server Compact databases // Uncomment this line and replace CONTEXT_NAME with the name of your DbContext if you are // using your DbContext to create and manage your database DbDatabase.SetInitializer(new CreateCeDatabaseIfNotExists<PersonContext>()); } } Now our database and entity framework are set up, so we can expose data via WCF Data Services. Note: This is a bare-bones implementation with no administration screens. If you'd like to see how those are added, check out The Full Stack screencast series. Creating the oData Service using WCF Data Services Add a new WCF Data Service to the project (right-click the project / Add New Item / Web / WCF Data Service). We’ll be exposing all the data as read/write.  Remember to reconfigure to control and minimize access as appropriate for your own application. Open the code behind for your service. In our case, the service was called PersonTestDataService.svc so the code behind class file is PersonTestDataService.svc.cs. using System.Data.Services; using System.Data.Services.Common; using System.ServiceModel; using DeadSimpleServer.Models; namespace DeadSimpleServer { [ServiceBehavior( IncludeExceptionDetailInFaults = true )] public class PersonTestDataService : DataService<PersonContext> { // This method is called only once to initialize service-wide policies. public static void InitializeService( DataServiceConfiguration config ) { config.SetEntitySetAccessRule( "*", EntitySetRights.All ); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; config.UseVerboseErrors = true; } } } We're enabling a few additional settings to make it easier to debug if you run into trouble. The ServiceBehavior attribute is set to include exception details in faults, and we're using verbose errors. You can remove both of these when your service is working, as your public production service shouldn't be revealing exception information. You can view the output of the service by running the application and browsing to http://localhost:[portnumber]/PersonTestDataService.svc/: <service xml:base="http://localhost:49786/PersonTestDataService.svc/" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:app="http://www.w3.org/2007/app" xmlns="http://www.w3.org/2007/app"> <workspace> <atom:title>Default</atom:title> <collection href="People"> <atom:title>People</atom:title> </collection> </workspace> </service> This indicates that the service exposes one collection, which is accessible by browsing to http://localhost:[portnumber]/PersonTestDataService.svc/People <?xml version="1.0" encoding="iso-8859-1" standalone="yes"?> <feed xml:base=http://localhost:49786/PersonTestDataService.svc/ xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns="http://www.w3.org/2005/Atom"> <title type="text">People</title> <id>http://localhost:49786/PersonTestDataService.svc/People</id> <updated>2010-12-29T01:01:50Z</updated> <link rel="self" title="People" href="People" /> <entry> <id>http://localhost:49786/PersonTestDataService.svc/People(1)</id> <title type="text"></title> <updated>2010-12-29T01:01:50Z</updated> <author> <name /> </author> <link rel="edit" title="Person" href="People(1)" /> <category term="DeadSimpleServer.Models.Person" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:ID m:type="Edm.Int32">1</d:ID> <d:Name>George Washington</d:Name> </m:properties> </content> </entry> <entry> ... </entry> </feed> Let's recap what we've done so far. But enough with services and XML - let's get this into our Windows Phone client application. Creating the DataServiceContext for the Client Use the latest DataSvcUtil.exe from http://odata.codeplex.com. As of today, that's in this download: http://odata.codeplex.com/releases/view/54698 You need to run it with a few options: /uri - This will point to the service URI. In this case, it's http://localhost:59342/PersonTestDataService.svc  Pick up the port number from your running server (e.g., the server formerly known as Cassini). /out - This is the DataServiceContext class that will be generated. You can name it whatever you'd like. /Version - should be set to 2.0 /DataServiceCollection - Include this flag to generate collections derived from the DataServiceCollection base, which brings in all the ObservableCollection goodness that handles your INotifyPropertyChanged events for you. Here's the console session from when we ran it: <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> Next, to keep things simple, change the Binding on the two TextBlocks within the DataTemplate to Name and ID, <ListBox x:Name="MainListBox" Margin="0,0,-12,0" ItemsSource="{Binding}" SelectionChanged="MainListBox_SelectionChanged"> <ListBox.ItemTemplate> <DataTemplate> <StackPanel Margin="0,0,0,17" Width="432"> <TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextExtraLargeStyle}" /> <TextBlock Text="{Binding ID}" TextWrapping="Wrap" Margin="12,-6,12,0" Style="{StaticResource PhoneTextSubtleStyle}" /> </StackPanel> </DataTemplate> </ListBox.ItemTemplate> </ListBox> Getting The Context In the code-behind you’ll first declare a member variable to hold the context from the Entity Framework. This is named using convention over configuration. The db type is Person and the context is of type PersonContext, You initialize it by providing the URI, in this case using the URL obtained from the Cassini web server, PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); Create a second member variable of type DataServiceCollection<Person> but do not initialize it, DataServiceCollection<Person> people; In the constructor you’ll initialize the DataServiceCollection using the PersonContext, public MainPage() { InitializeComponent(); people = new DataServiceCollection<Person>( context ); Finally, you’ll load the people collection using the LoadAsync method, passing in the fully specified URI for the People collection in the web service, people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); Note that this method runs asynchronously and when it is finished the people  collection is already populated. Thus, since we didn’t need or want to override any of the behavior we don’t implement the LoadCompleted. You can use the LoadCompleted event if you need to do any other UI updates, but you don't need to. The final code is as shown below: using System; using System.Data.Services.Client; using System.Windows; using System.Windows.Controls; using DeadSimpleServer.Models; using Microsoft.Phone.Controls; namespace WindowsPhoneODataTest { public partial class MainPage : PhoneApplicationPage { PersonContext context = new PersonContext( new Uri( "http://localhost:49786/PersonTestDataService.svc/" ) ); DataServiceCollection<Person> people; // Constructor public MainPage() { InitializeComponent(); // Set the data context of the listbox control to the sample data // DataContext = App.ViewModel; people = new DataServiceCollection<Person>( context ); people.LoadAsync( new Uri( "http://localhost:49786/PersonTestDataService.svc/People" ) ); DataContext = people; this.Loaded += new RoutedEventHandler( MainPage_Loaded ); } // Handle selection changed on ListBox private void MainListBox_SelectionChanged( object sender, SelectionChangedEventArgs e ) { // If selected index is -1 (no selection) do nothing if ( MainListBox.SelectedIndex == -1 ) return; // Navigate to the new page NavigationService.Navigate( new Uri( "/DetailsPage.xaml?selectedItem=" + MainListBox.SelectedIndex, UriKind.Relative ) ); // Reset selected index to -1 (no selection) MainListBox.SelectedIndex = -1; } // Load data for the ViewModel Items private void MainPage_Loaded( object sender, RoutedEventArgs e ) { if ( !App.ViewModel.IsDataLoaded ) { App.ViewModel.LoadData(); } } } } With people populated we can set it as the DataContext and run the application; you’ll find that the Name and ID are displayed in the list on the Mainpage. Here's how the pieces in the client fit together: Complete source code available here

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  • Oracle Support Master Note for Troubleshooting Advanced Queuing and Oracle Streams Propagation Issues (Doc ID 233099.1)

    - by faye.todd(at)oracle.com
    Master Note for Troubleshooting Advanced Queuing and Oracle Streams Propagation Issues (Doc ID 233099.1) Copyright (c) 2010, Oracle Corporation. All Rights Reserved. In this Document  Purpose  Last Review Date  Instructions for the Reader  Troubleshooting Details     1. Scope and Application      2. Definitions and Classifications     3. How to Use This Guide     4. Basic AQ Propagation Troubleshooting     5. Additional Troubleshooting Steps for AQ Propagation of User-Enqueued and Dequeued Messages     6. Additional Troubleshooting Steps for Propagation in an Oracle Streams Environment     7. Performance Issues  References Applies to: Oracle Server - Enterprise Edition - Version: 8.1.7.0 to 11.2.0.2 - Release: 8.1.7 to 11.2Information in this document applies to any platform. Purpose This document presents a step-by-step methodology for troubleshooting and resolving problems with Advanced Queuing Propagation in both Streams and basic Advanced Queuing environments. It also serves as a master reference for other more specific notes on Oracle Streams Propagation and Advanced Queuing Propagation issues. Last Review Date December 20, 2010 Instructions for the Reader A Troubleshooting Guide is provided to assist in debugging a specific issue. When possible, diagnostic tools are included in the document to assist in troubleshooting. Troubleshooting Details 1. Scope and Application This note is intended for Database Administrators of Oracle databases where issues are being encountered with propagating messages between advanced queues, whether the queues are used for user-created messaging systems or for Oracle Streams. It contains troubleshooting steps and links to notes for further problem resolution.It can also be used a template to document a problem when it is necessary to engage Oracle Support Services. Knowing what is NOT happening can frequently speed up the resolution process by focusing solely on the pertinent problem area. This guide is divided into five parts: Section 2: Definitions and Classifications (discusses the different types and features of propagations possible - helpful for understanding the rest of the guide) Section 3: How to Use this Guide (to be used as a start part for determining the scope of the problem and what sections to consult) Section 4. Basic AQ propagation troubleshooting (applies to both AQ propagation of user enqueued and dequeued messages as well as Oracle Streams propagations) Section 5. Additional troubleshooting steps for AQ propagation of user enqueued and dequeued messages Section 6. Additional troubleshooting steps for Oracle Streams propagation Section 7. Performance issues 2. Definitions and Classifications Given the potential scope of issues that can be encountered with AQ propagation, the first recommended step is to do some basic diagnosis to determine the type of problem that is being encountered. 2.1. What Type of Propagation is Being Used? 2.1.1. Buffered Messaging For an advanced queue, messages can be maintained on disk (persistent messaging) or in memory (buffered messaging). To determine if a queue is buffered or not, reference the GV_$BUFFERED_QUEUES view. If the queue does not appear in this view, it is persistent. 2.1.2. Propagation mode - queue-to-dblink vs queue-to-queue As of 10.2, an AQ propagation can also be defined as queue-to-dblink, or queue-to-queue: queue-to-dblink: The propagation delivers messages or events from the source queue to all subscribing queues at the destination database identified by the dblink. A single propagation schedule is used to propagate messages to all subscribing queues. Hence any changes made to this schedule will affect message delivery to all the subscribing queues. This mode does not support multiple propagations from the same source queue to the same target database. queue-to-queue: Added in 10.2, this propagation mode delivers messages or events from the source queue to a specific destination queue identified on the database link. This allows the user to have fine-grained control on the propagation schedule for message delivery. This new propagation mode also supports transparent failover when propagating to a destination Oracle RAC system. With queue-to-queue propagation, you are no longer required to re-point a database link if the owner instance of the queue fails on Oracle RAC. This mode supports multiple propagations to the same target database if the target queues are different. The default is queue-to-dblink. To verify if queue-to-queue propagation is being used, in non-Streams environments query DBA_QUEUE_SCHEDULES.DESTINATION - if a remote queue is listed along with the remote database link, then queue-to-queue propagation is being used. For Streams environments, the DBA_PROPAGATION.QUEUE_TO_QUEUE column can be checked.See the following note for a method to switch between the two modes:Document 827473.1 How to alter propagation from queue-to-queue to queue-to-dblink 2.1.3. Combined Capture and Apply (CCA) for Streams In 11g Oracle Streams environments, an optimization called Combined Capture and Apply (CCA) is implemented by default when possible. Although a propagation is configured in this case, Streams does not use it; instead it passes information directly from capture to an apply receiver. To see if CCA is in use: COLUMN CAPTURE_NAME HEADING 'Capture Name' FORMAT A30COLUMN OPTIMIZATION HEADING 'CCA Mode?' FORMAT A10SELECT CAPTURE_NAME, DECODE(OPTIMIZATION,0, 'No','Yes') OPTIMIZATIONFROM V$STREAMS_CAPTURE; Also, see the following note:Document 463820.1 Streams Combined Capture and Apply in 11g 2.2. Queue Table Compatibility There are three types of queue table compatibility. In more recent databases, queue tables may be present in all three modes of compatibility: 8.0 - earliest version, deprecated in 10.2 onwards 8.1 - support added for RAC, asynchronous notification, secure queues, queue level access control, rule-based subscribers, separate storage of history information 10.0 - if the database is in 10.1-compatible mode, then the default value for queue table compatibility is 10.0 2.3. Single vs Multiple Consumer Queue Tables If more than one recipient can dequeue a message from a queue, then its queue table is multiple consumer. You can propagate messages from a multiple-consumer queue to a single-consumer queue. Propagation from a single-consumer queue to a multiple-consumer queue is not possible. 3. How to Use This Guide 3.1. Are Messages Being Propagated at All, or is the Propagation Just Slow? Run the following query on the source database for the propagation (assuming that it is running): select TOTAL_NUMBER from DBA_QUEUE_SCHEDULES where QNAME='<source_queue_name>'; If TOTAL_NUMBER is increasing, then propagation is most likely functioning, although it may be slow. For performance issues, see Section 7. 3.2. Propagation Between Persistent User-Created Queues See Sections 4 and 5 (and optionally Section 6 if performance is an issue). 3.3. Propagation Between Buffered User-Created Queues See Sections 4, 5, and 6 (and optionally Section 7 if performance is an issue). 3.4. Propagation between Oracle Streams Queues (without Combined Capture and Apply (CCA) Optimization) See Sections 4 and 6 (and optionally Section 7 if performance is an issue). 3.5. Propagation between Oracle Streams Queues (with Combined Capture and Apply (CCA) Optimization) Although an AQ propagation is not used directly in this case, some characteristics of the message transfer are inferred from the propagation parameters used. Some parts of Sections 4 and 6 still apply. 3.6. Messaging Gateway Propagations This note does not apply to Messaging Gateway propagations. 4. Basic AQ Propagation Troubleshooting 4.1. Double-check Your Code Make sure that you are consistent in your usage of the database link(s) names, queue names, etc. It may be useful to plot a diagram of which queues are connected via which database links to make sure that the logical structure is correct. 4.2. Verify that Job Queue Processes are Running 4.2.1. Versions 10.2 and Lower - DBA_JOBS Package For versions 10.2 and lower, a scheduled propagation is managed by DBMS_JOB package. The propagation is performed by job queue process background processes. Therefore we need to verify that there are sufficient processes available for the propagation process. We should have at least 4 job queue processes running and preferably more depending on the number of other jobs running in the database. It should be noted that for AQ specific work, AQ will only ever use half of the job queue processes available.An issue caused by an inadequate job queue processes parameter setting is described in the following note:Document 298015.1 Kwqjswproc:Excep After Loop: Assigning To Self 4.2.1.1. Job Queue Processes in Initalization Parameter File The parameter JOB_QUEUE_PROCESSES in the init.ora/spfile should be > 0. The value can be changed dynamically via connect / as sysdbaalter system set JOB_QUEUE_PROCESSES=10; 4.2.1.2. Job Queue Processes in Memory The following command will show how many job queue processes are currentlyin use by this instance (this may be different than what is in the init.ora/spfile): connect / as sysdbashow parameter job; 4.2.1.3. OS PIDs Corresponding to Job Queue Processes Identify the operating system process ids (spids) of job queue processes involved in propagation via select p.SPID, p.PROGRAM from V$PROCESS p, DBA_JOBS_RUNNING jr, V$SESSION s, DBA_JOBS j where s.SID=jr.SID and s.PADDR=p.ADDR and jr.JOB=j.JOBand j.WHAT like '%sys.dbms_aqadm.aq$_propaq(job)%'; and these SPIDs can be used to check at the operating system level that they exist.In 8i a job queue process will have a name similar to: ora_snp1_<instance_name>.In 9i onwards you will see a coordinator process: ora_cjq0_ and multiple slave processes: ora_jnnn_<instance_name>, where nnn is an integer between 1 and 999. 4.2.2. Version 11.1 and Above - Oracle Scheduler In version 11.1 and above, Oracle Scheduler is used to perform AQ and Streams propagations. Oracle Scheduler automatically tunes the number of slave processes for these jobs based on the load on the computer system, and the JOB_QUEUE_PROCESSES initialization parameter is only used to specify the maximum number of slave processes. Therefore, the JOB_QUEUE_PROCESSES initialization parameter does not need to be set (it defaults to a very high number), unless you want to limit the number of slaves that can be created. If JOB_QUEUE_PROCESSES = 0, no propagation jobs will run.See the following note for a discussion of Oracle Streams 11g and Oracle Scheduler:Document 1083608.1 11g Streams and Oracle Scheduler 4.2.2.1. Job Queue Processes in Initalization Parameter File The parameter JOB_QUEUE_PROCESSES in the init.ora/spfile should be > 0, and preferably be left at its default value. The value can be changed dynamically via connect / as sysdbaalter system set JOB_QUEUE_PROCESSES=10; To set the JOB_QUEUE_PROCESSES parameter to its default value, run: connect / as sysdbaalter system reset JOB_QUEUE_PROCESSES; and then bounce the instance. 4.2.2.2. Job Queue Processes in Memory The following command will show how many job queue processes are currently in use by this instance (this may be different than what is in the init.ora/spfile): connect / as sysdbashow parameter job; 4.2.2.3. OS PIDs Corresponding to Job Queue Processes Identify the operating system process ids (SPIDs) of job queue processes involved in propagation via col PROGRAM for a30select p.SPID, p.PROGRAM, j.JOB_namefrom v$PROCESS p, DBA_SCHEDULER_RUNNING_JOBS jr, V$SESSION s, DBA_SCHEDULER_JOBS j where s.SID=jr.SESSION_ID and s.PADDR=p.ADDRand jr.JOB_name=j.JOB_NAME and j.JOB_NAME like '%AQ_JOB$_%'; and these SPIDs can be used to check at the operating system level that they exist.You will see a coordinator process: ora_cjq0_ and multiple slave processes: ora_jnnn_<instance_name>, where nnn is an integer between 1 and 999. 4.3. Check the Alert Log and Any Associated Trace Files The first place to check for propagation failures is the alert logs at all sites (local and if relevant all remote sites). When a job queue process attempts to execute a schedule and fails it will always write an error stack to the alert log. This error stack will also be written in a job queue process trace file, which will be written to the BACKGROUND_DUMP_DEST location for 10.2 and below, and in the DIAGNOSTIC_DEST location for 11g. The fact that errors are written to the alert log demonstrates that the schedule is executing. This means that the problem could be with the set up of the schedule. In this example the ORA-02068 demonstrates that the failure was at the remote site. Further investigation revealed that the remote database was not open, hence the ORA-03114 error. Starting the database resolved the problem. Thu Feb 14 10:40:05 2002 Propagation Schedule for (AQADM.MULTIPLEQ, SHANE816.WORLD) encountered following error:ORA-04052: error occurred when looking up Remote object [email protected]: error occurred at recursive SQL level 4ORA-02068: following severe error from SHANE816ORA-03114: not connected to ORACLEORA-06512: at "SYS.DBMS_AQADM_SYS", line 4770ORA-06512: at "SYS.DBMS_AQADM", line 548ORA-06512: at line 1 Other potential errors that may be written to the alert log can be found in the following notes:Document 827184.1 AQ Propagation with CLOB data types Fails with ORA-22990 (11.1)Document 846297.1 AQ Propagation Fails : ORA-00600[kope2upic2954] or Ora-00600[Kghsstream_copyn] (10.2, 11.1)Document 731292.1 ORA-25215 Reported on Local Propagation When Using Transformation with ANYDATA queue tables (10.2, 11.1, 11.2)Document 365093.1 ORA-07445 [kwqppay2aqe()+7360] Reported on Propagation of a Transformed Message (10.1, 10.2)Document 219416.1 Advanced Queuing Propagation Fails with ORA-22922 (9.0)Document 1203544.1 AQ Propagation Aborted with ORA-600 [ociksin: invalid status] on SYS.DBMS_AQADM_SYS.AQ$_PROPAGATION_PROCEDURE After Upgrade (11.1, 11.2)Document 1087324.1 ORA-01405 ORA-01422 reported by Advanced Queuing Propagation schedules after RAC reconfiguration (10.2)Document 1079577.1 Advanced Queuing Propagation Fails With "ORA-22370 incorrect usage of method" (9.2, 10.2, 11.1, 11.2)Document 332792.1 ORA-04061 error relating to SYS.DBMS_PRVTAQIP reported when setting up Statspack (8.1, 9.0, 9.2, 10.1)Document 353325.1 ORA-24056: Internal inconsistency for QUEUE <queue_name> and destination <dblink> (8.1, 9.0, 9.2, 10.1, 10.2, 11.1, 11.2)Document 787367.1 ORA-22275 reported on Propagating Messages with LOB component when propagating between 10.1 and 10.2 (10.1, 10.2)Document 566622.1 ORA-22275 when propagating >4K AQ$_JMS_TEXT_MESSAGEs from 9.2.0.8 to 10.2.0.1 (9.2, 10.1)Document 731539.1 ORA-29268: HTTP client error 401 Unauthorized Error when the AQ Servlet attempts to Propagate a message via HTTP (9.0, 9.2, 10.1, 10.2, 11.1)Document 253131.1 Concurrent Writes May Corrupt LOB Segment When Using Auto Segment Space Management (ORA-1555) (9.2)Document 118884.1 How to unschedule a propagation schedule stuck in pending stateDocument 222992.1 DBMS_AQADM.DISABLE_PROPAGATION_SCHEDULE Returns ORA-24082Document 282987.1 Propagated Messages marked UNDELIVERABLE after Drop and Recreate Of Remote QueueDocument 1204080.1 AQ Propagation Failing With ORA-25329 After Upgraded From 8i or 9i to 10g or 11g.Document 1233675.1 AQ Propagation stops after upgrade to 11.2.0.1 ORA-30757 4.3.1. Errors Related to Incorrect Network Configuration The most common propagation errors result from an incorrect network configuration. The list below contains common errors caused by tnsnames.ora file or database links being configured incorrectly: - ORA-12154: TNS:could not resolve service name- ORA-12505: TNS:listener does not currently know of SID given in connect descriptor- ORA-12514: TNS:listener could not resolve SERVICE_NAME - ORA-12541: TNS-12541 TNS:no listener 4.4. Check the Database Links Exist and are Functioning Correctly For schedules to remote databases confirm the database link exists via. SQL> col DBLINK for a45SQL> select QNAME, NVL(REGEXP_SUBSTR(DESTINATION, '[^@]+', 1, 2), DESTINATION) dblink2 from DBA_QUEUE_SCHEDULES3 where MESSAGE_DELIVERY_MODE = 'PERSISTENT';QNAME DBLINK------------------------------ ---------------------------------------------MY_QUEUE ORCL102B.WORLD Connect as the owner of the link and select across it to verify it works and connects to the database we expect. i.e. select * from ALL_QUEUES@ ORCL102B.WORLD; You need to ensure that the userid that scheduled the propagation (using DBMS_AQADM.SCHEDULE_PROPAGATION or DBMS_PROPAGATION_ADM.CREATE_PROPAGATION if using Streams) has access to the database link for the destination. 4.5. Has Propagation Been Correctly Scheduled? Check that the propagation schedule has been created and that a job queue process has been assigned. Look for the entry in DBA_QUEUE_SCHEDULES and SYS.AQ$_SCHEDULES for your schedule. For 10g and below, check that it has a JOBNO entry in SYS.AQ$_SCHEDULES, and that there is an entry in DBA_JOBS with that JOBNO. For 11g and above, check that the schedule has a JOB_NAME entry in SYS.AQ$_SCHEDULES, and that there is an entry in DBA_SCHEDULER_JOBS with that JOB_NAME. Check the destination is as intended and spelled correctly. SQL> select SCHEMA, QNAME, DESTINATION, SCHEDULE_DISABLED, PROCESS_NAME from DBA_QUEUE_SCHEDULES;SCHEMA QNAME DESTINATION S PROCESS------- ---------- ------------------ - -----------AQADM MULTIPLEQ AQ$_LOCAL N J000 AQ$_LOCAL in the destination column shows that the queue to which we are propagating to is in the same database as the source queue. If the propagation was to a remote (different) database, a database link will be in the DESTINATION column. The entry in the SCHEDULE_DISABLED column, N, means that the schedule is NOT disabled. If Y (yes) appears in this column, propagation is disabled and the schedule will not be executed. If not using Oracle Streams, propagation should resume once you have enabled the schedule by invoking DBMS_AQADM.ENABLE_PROPAGATION_SCHEDULE (for 10.2 Oracle Streams and above, the DBMS_PROPAGATION_ADM.START_PROPAGATION procedure should be used). The PROCESS_NAME is the name of the job queue process currently allocated to execute the schedule. This process is allocated dynamically at execution time. If the PROCESS_NAME column is null (empty) the schedule is not currently executing. You may need to execute this statement a number of times to verify if a process is being allocated. If a process is at some time allocated to the schedule, it is attempting to execute. SQL> select SCHEMA, QNAME, LAST_RUN_DATE, NEXT_RUN_DATE from DBA_QUEUE_SCHEDULES;SCHEMA QNAME LAST_RUN_DATE NEXT_RUN_DATE------ ----- ----------------------- ----------------------- AQADM MULTIPLEQ 13-FEB-2002 13:18:57 13-FEB-2002 13:20:30 In 11g, these dates are expressed in TIMESTAMP WITH TIME ZONE datatypes. If the NEXT_RUN_DATE and NEXT_RUN_TIME columns are null when this statement is executed, the scheduled propagation is currently in progress. If they never change it would suggest that the schedule itself is never executing. If the next scheduled execution is too far away, change the NEXT_TIME parameter of the schedule so that schedules are executed more frequently (assuming that the window is not set to be infinite). Parameters of a schedule can be changed using the DBMS_AQADM.ALTER_PROPAGATION_SCHEDULE call. In 10g and below, scheduling propagation posts a job in the DBA_JOBS view. The columns are more or less the same as DBA_QUEUE_SCHEDULES so you just need to recognize the job and verify that it exists. SQL> select JOB, WHAT from DBA_JOBS where WHAT like '%sys.dbms_aqadm.aq$_propaq(job)%';JOB WHAT---- ----------------- 720 next_date := sys.dbms_aqadm.aq$_propaq(job); For 11g, scheduling propagation posts a job in DBA_SCHEDULER_JOBS instead: SQL> select JOB_NAME from DBA_SCHEDULER_JOBS where JOB_NAME like 'AQ_JOB$_%';JOB_NAME------------------------------AQ_JOB$_41 If no job exists, check DBA_QUEUE_SCHEDULES to make sure that the schedule has not been disabled. For 10g and below, the job number is dynamic for AQ propagation schedules. The procedure that is executed to expedite a propagation schedule runs, removes itself from DBA_JOBS, and then reposts a new job for the next scheduled propagation. The job number should therefore always increment unless the schedule has been set up to run indefinitely. 4.6. Is the Schedule Executing but Failing to Complete? Run the following query: SQL> select FAILURES, LAST_ERROR_MSG from DBA_QUEUE_SCHEDULES;FAILURES LAST_ERROR_MSG------------ -----------------------1 ORA-25207: enqueue failed, queue AQADM.INQ is disabled from enqueueingORA-02063: preceding line from SHANE816 The failures column shows how many times we have attempted to execute the schedule and failed. Oracle will attempt to execute the schedule 16 times after which it will be removed from the DBA_JOBS or DBA_SCHEDULER_JOBS view and the schedule will become disabled. The column DBA_QUEUE_SCHEDULES.SCHEDULE_DISABLED will show 'Y'. For 11g and above, the DBA_SCHEDULER_JOBS.STATE column will show 'BROKEN' for the job corresponding to DBA_QUEUE_SCHEDULES.JOB_NAME. Prior to 10g the back off algorithm for failures was exponential, whereas from 10g onwards it is linear. The propagation will become disabled on the 17th attempt. Only the last execution failure will be reflected in the LAST_ERROR_MSG column. That is, if the schedule fails 5 times for 5 different reasons, only the last set of errors will be recorded in DBA_QUEUE_SCHEDULES. Any errors need to be resolved to allow propagation to continue. If propagation has also become disabled due to 17 failures, first resolve the reason for the error and then re-enable the schedule using the DBMS_AQADM.ENABLE_PROPAGATION_SCHEDULE procedure, or DBMS_PROPAGATION_ADM.START_PROPAGATION if using 10.2 or above Oracle Streams. As soon as the schedule executes successfully the error message entries will be deleted. Oracle does not keep a history of past failures. However, when using Oracle Streams, the errors will be retained in the DBA_PROPAGATION view even after the schedule resumes successfully. See the following note for instructions on how to clear out the errors from the DBA_PROPAGATION view:Document 808136.1 How to clear the old errors from DBA_PROPAGATION view?If a schedule is active and no errors are being reported then the source queue may not have any messages to be propagated. 4.7. Do the Propagation Notification Queue Table and Queue Exist? Check to see that the propagation notification queue table and queue exist and are enabled for enqueue and dequeue. Propagation makes use of the propagation notification queue for handling propagation run-time events, and the messages in this queue are stored in a SYS-owned queue table. This queue should never be stopped or dropped and the corresponding queue table never be dropped. 10g and belowThe propagation notification queue table is of the format SYS.AQ$_PROP_TABLE_n, where 'n' is the RAC instance number, i.e. '1' for a non-RAC environment. This queue and queue table are created implicitly when propagation is first scheduled. If propagation has been scheduled and these objects do not exist, try unscheduling and rescheduling propagation. If they still do not exist contact Oracle Support. SQL> select QUEUE_TABLE from DBA_QUEUE_TABLES2 where QUEUE_TABLE like '%PROP_TABLE%' and OWNER = 'SYS';QUEUE_TABLE------------------------------AQ$_PROP_TABLE_1SQL> select NAME, ENQUEUE_ENABLED, DEQUEUE_ENABLED2 from DBA_QUEUES where owner='SYS'3 and QUEUE_TABLE like '%PROP_TABLE%';NAME ENQUEUE DEQUEUE------------------------------ ------- -------AQ$_PROP_NOTIFY_1 YES YESAQ$_AQ$_PROP_TABLE_1_E NO NO If the AQ$_PROP_NOTIFY_1 queue is not enabled for enqueue or dequeue, it should be so enabled using DBMS_AQADM.START_QUEUE. However, the exception queue AQ$_AQ$_PROP_TABLE_1_E should not be enabled for enqueue or dequeue.11g and aboveThe propagation notification queue table is of the format SYS.AQ_PROP_TABLE, and is created when the database is created. If they do not exist, contact Oracle Support. SQL> select QUEUE_TABLE from DBA_QUEUE_TABLES2 where QUEUE_TABLE like '%PROP_TABLE%' and OWNER = 'SYS';QUEUE_TABLE------------------------------AQ_PROP_TABLESQL> select NAME, ENQUEUE_ENABLED, DEQUEUE_ENABLED2 from DBA_QUEUES where owner='SYS'3 and QUEUE_TABLE like '%PROP_TABLE%';NAME ENQUEUE DEQUEUE------------------------------ ------- -------AQ_PROP_NOTIFY YES YESAQ$_AQ_PROP_TABLE_E NO NO If the AQ_PROP_NOTIFY queue is not enabled for enqueue or dequeue, it should be so enabled using DBMS_AQADM.START_QUEUE. However, the exception queue AQ$_AQ$_PROP_TABLE_E should not be enabled for enqueue or dequeue. 4.8. Does the Remote Queue Exist and is it Enabled for Enqueueing? Check that the remote queue the propagation is transferring messages to exists and is enabled for enqueue: SQL> select DESTINATION from USER_QUEUE_SCHEDULES where QNAME = 'OUTQ';DESTINATION-----------------------------------------------------------------------------"AQADM"."INQ"@M2V102.ESSQL> select OWNER, NAME, ENQUEUE_ENABLED, DEQUEUE_ENABLED from [email protected];OWNER NAME ENQUEUE DEQUEUE-------- ------ ----------- -----------AQADM INQ YES YES 4.9. Do the Target and Source Database Charactersets Differ? If a message fails to propagate, check the database charactersets of the source and target databases. Investigate whether the same message can propagate between the databases with the same characterset or it is only a particular combination of charactersets which causes a problem. 4.10. Check the Queue Table Type Agreement Propagation is not possible between queue tables which have types that differ in some respect. One way to determine if this is the case is to run the DBMS_AQADM.VERIFY_QUEUE_TYPES procedure for the two queues that the propagation operates on. If the types do not agree, DBMS_AQADM.VERIFY_QUEUE_TYPES will return '0'.For AQ propagation between databases which have different NLS_LENGTH_SEMANTICS settings, propagation will not work, unless the queues are Oracle Streams ANYDATA queues.See the following notes for issues caused by lack of type agreement:Document 1079577.1 Advanced Queuing Propagation Fails With "ORA-22370: incorrect usage of method"Document 282987.1 Propagated Messages marked UNDELIVERABLE after Drop and Recreate Of Remote QueueDocument 353754.1 Streams Messaging Propagation Fails between Single and Multi-byte Charactersets when using Chararacter Length Semantics in the ADT 4.11. Enable Propagation Tracing 4.11.1. System Level This is set it in the init.ora/spfile as follows: event="24040 trace name context forever, level 10" and restart the instanceThis event cannot be set dynamically with an alter system command until version 10.2: SQL> alter system set events '24040 trace name context forever, level 10'; To unset the event: SQL> alter system set events '24040 trace name context off'; Debugging information will be logged to job queue trace file(s) (jnnn) as propagation takes place. You can check the trace file for errors, and for statements indicating that messages have been sent. For the most part the trace information is understandable. This trace should also be uploaded to Oracle Support if a service request is created. 4.11.2. Attaching to a Specific Process We can also attach to an existing job queue processes that is running a propagation schedule and trace it individually using the oradebug utility, as follows:10.2 and below connect / as sysdbaselect p.SPID, p.PROGRAM from v$PROCESS p, DBA_JOBS_RUNNING jr, V$SESSION s, DBA_JOBS j where s.SID=jr.SID and s.PADDR=p.ADDR and jr.JOB=j.JOB and j.WHAT like '%sys.dbms_aqadm.aq$_propaq(job)%';-- For the process id (SPID) attach to it via oradebug and generate the following traceoradebug setospid <SPID>oradebug unlimitoradebug Event 10046 trace name context forever, level 12oradebug Event 24040 trace name context forever, level 10-- Trace the process for 5 minutesoradebug Event 10046 trace name context offoradebug Event 24040 trace name context off-- The following command returns the pathname/filename to the file being written tooradebug tracefile_name 11g connect / as sysdbacol PROGRAM for a30select p.SPID, p.PROGRAM, j.JOB_NAMEfrom v$PROCESS p, DBA_SCHEDULER_RUNNING_JOBS jr, V$SESSION s, DBA_SCHEDULER_JOBS j where s.SID=jr.SESSION_ID and s.PADDR=p.ADDR and jr.JOB_NAME=j.JOB_NAME and j.JOB_NAME like '%AQ_JOB$_%';-- For the process id (SPID) attach to it via oradebug and generate the following traceoradebug setospid <SPID>oradebug unlimitoradebug Event 10046 trace name context forever, level 12oradebug Event 24040 trace name context forever, level 10-- Trace the process for 5 minutesoradebug Event 10046 trace name context offoradebug Event 24040 trace name context off-- The following command returns the pathname/filename to the file being written tooradebug tracefile_name 4.11.3. Further Tracing The previous tracing steps only trace the job queue process executing the propagation on the source. At times it is useful to trace the propagation receiver process (the session which is enqueueing the messages into the target queue) on the target database which is associated with the job queue process on the source database.These following queries provide ways of identifying the processes involved in propagation so that you can attach to them via oradebug to generate trace information.In order to identify the propagation receiver process you need to execute the query as a user with privileges to access the v$ views in both the local and remote databases so the database link must connect as a user with those privileges in the remote database. The <DBLINK> in the queries should be replaced by the appropriate database link.The queries have two forms due to the differences between operating systems. The value returned by 'Rem Process' is the operating system identifier of the propagation receiver on the remote database. Once identified, this process can be attached to and traced on the remote database using the commands given in Section 4.11.2.10.2 and below - Windows select pl.SPID "JobQ Process", pl.PROGRAM, sr.PROCESS "Rem Process" from v$PROCESS pl, DBA_JOBS_RUNNING jr, V$SESSION s, DBA_JOBS j, V$SESSION@<DBLINK> sr where s.SID=jr.SID and s.PADDR=pl.ADDR and jr.JOB=j.JOB and j.WHAT like '%sys.dbms_aqadm.aq$_propaq(job)%' and pl.SPID=substr(sr.PROCESS, instr(sr.PROCESS,':')+1); 10.2 and below - Unix select pl.SPID "JobQ Process", pl.PROGRAM, sr.PROCESS "Rem Process" from V$PROCESS pl, DBA_JOBS_RUNNING jr, V$SESSION s, DBA_JOBS j, V$SESSION@<DBLINK> sr where s.SID=jr.SID and s.PADDR=pl.ADDR and jr.JOB=j.JOB and j.WHAT like '%sys.dbms_aqadm.aq$_propaq(job)%' and pl.SPID=sr.PROCESS; 11g - Windows select pl.SPID "JobQ Process", pl.PROGRAM, sr.PROCESS "Rem Process" from V$PROCESS pl, DBA_SCHEDULER_RUNNING_JOBS jr, V$SESSION s, DBA_SCHEDULER_JOBS j, V$SESSION@<DBLINK> sr where s.SID=jr.SESSION_ID and s.PADDR=pl.ADDR and jr.JOB_NAME=j.JOB_NAME and j.JOB_NAME like '%AQ_JOB$_%%' and pl.SPID=substr(sr.PROCESS, instr(sr.PROCESS,':')+1); 11g - Unix select pl.SPID "JobQ Process", pl.PROGRAM, sr.PROCESS "Rem Process" from V$PROCESS pl, DBA_SCHEDULER_RUNNING_JOBS jr, V$SESSION s, DBA_SCHEDULER_JOBS j, V$SESSION@<DBLINK> sr where s.SID=jr.SESSION_ID and s.PADDR=pl.ADDR and jr.JOB_NAME=j.JOB_NAME and j.JOB_NAME like '%AQ_JOB$_%%' and pl.SPID=sr.PROCESS;   5. Additional Troubleshooting Steps for AQ Propagation of User-Enqueued and Dequeued Messages 5.1. Check the Privileges of All Users Involved Ensure that the owner of the database link has the necessary privileges on the aq packages. SQL> select TABLE_NAME, PRIVILEGE from USER_TAB_PRIVS;TABLE_NAME PRIVILEGE------------------------------ ----------------------------------------DBMS_LOCK EXECUTEDBMS_AQ EXECUTEDBMS_AQADM EXECUTEDBMS_AQ_BQVIEW EXECUTEQT52814_BUFFER SELECT Note that when queue table is created, a view called QT<nnn>_BUFFER is created in the SYS schema, and the queue table owner is given SELECT privileges on it. The <nnn> corresponds to the object_id of the associated queue table. SQL> select * from USER_ROLE_PRIVS;USERNAME GRANTED_ROLE ADM DEF OS_------------------------------ ------------------------------ ---- ---- ---AQ_USER1 AQ_ADMINISTRATOR_ROLE NO YES NOAQ_USER1 CONNECT NO YES NOAQ_USER1 RESOURCE NO YES NO It is good practice to configure central AQ administrative user. All admin and processing jobs are created, executed and administered as this user. This configuration is not mandatory however, and the database link can be owned by any existing queue user. If this latter configuration is used, ensure that the connecting user has the necessary privileges on the AQ packages and objects involved. Privileges for an AQ Administrative user Execute on DBMS_AQADM Execute on DBMS_AQ Granted the AQ_ADMINISTRATOR_ROLE Privileges for an AQ user Execute on DBMS_AQ Execute on the message payload Enqueue privileges on the remote queue Dequeue privileges on the originating queue Privileges need to be confirmed on both sites when propagation is scheduled to remote destinations. Verify that the user ID used to login to the destination through the database link has been granted privileges to use AQ. 5.2. Verify Queue Payload Types AQ will not propagate messages from one queue to another if the payload types of the two queues are not verified to be equivalent. An AQ administrator can verify if the source and destination's payload types match by executing the DBMS_AQADM.VERIFY_QUEUE_TYPES procedure. The results of the type checking will be stored in the SYS.AQ$_MESSAGE_TYPES table. This table can be accessed using the object identifier OID of the source queue and the address database link of the destination queue, i.e. [schema.]queue_name[@destination]. Prior to Oracle 9i the payload (message type) had to be the same for all the queue tables involved in propagation. From Oracle9i onwards a transformation can be used so that payloads can be converted from one type to another. The following procedural call made on the source database can verify whether we can propagate between the source and the destination queue tables. connect aq_user1/[email protected] serverout onDECLARErc_value number;BEGINDBMS_AQADM.VERIFY_QUEUE_TYPES(src_queue_name => 'AQ_USER1.Q_1', dest_queue_name => 'AQ_USER2.Q_2',destination => 'dbl_aq_user2.es',rc => rc_value);dbms_output.put_line('rc_value code is '||rc_value);END;/ If propagation is possible then the return code value will be 1. If it is 0 then propagation is not possible and further investigation of the types and transformations used by and in conjunction with the queue tables is required. With regard to comparison of the types the following sql can be used to extract the DDL for a specific type with' %' changed appropriately on the source and target. This can then be compared for the source and target. SET LONG 20000 set pagesize 50 EXECUTE DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM, 'STORAGE',false); SELECT DBMS_METADATA.GET_DDL('TYPE',t.type_name) from user_types t WHERE t.type_name like '%'; EXECUTE DBMS_METADATA.SET_TRANSFORM_PARAM(DBMS_METADATA.SESSION_TRANSFORM, 'DEFAULT'); 5.3. Check Message State and Destination The first step in this process is to identify the queue table associated with the problem source queue. Although you schedule propagation for a specific queue, most of the meta-data associated with that queue is stored in the underlying queue table. The following statement finds the queue table for a given queue (note that this is a multiple-consumer queue table). SQL> select QUEUE_TABLE from DBA_QUEUES where NAME = 'MULTIPLEQ';QUEUE_TABLE --------------------MULTIPLEQTABLE For a small amount of messages in a multiple-consumer queue table, the following query can be run: SQL> select MSG_STATE, CONSUMER_NAME, ADDRESS from AQ$MULTIPLEQTABLE where QUEUE = 'MULTIPLEQ';MSG_STATE CONSUMER_NAME ADDRESS-------------- ----------------------- -------------READY AQUSER2 [email protected] AQUSER1READY AQUSER3 AQADM.INQ In this example we see 2 messages ready to be propagated to remote queues and 1 that is not. If the address column is blank, the message is not scheduled for propagation and can only be dequeued from the queue upon which it was enqueued. The MSG_STATE column values are discussed in Document 102330.1 Advanced Queueing MSG_STATE Values and their Interpretation. If the address column has a value, the message has been enqueued for propagation to another queue. The first row in the example includes a database link (@M2V102.ES). This demonstrates that the message should be propagated to a queue at a remote database. The third row does not include a database link so will be propagated to a queue that resides on the same database as the source queue. The consumer name is the intended recipient at the target queue. Note that we are not querying the base queue table directly; rather, we are querying a view that is available on top of every queue table, AQ$<queue_table_name>.A more realistic query in an environment where the queue table contains thousands of messages is8.0.3-compatible multiple-consumer queue table and all compatibility single-consumer queue tables select count(*), MSG_STATE, QUEUE from AQ$<queue_table_name>  group by MSG_STATE, QUEUE; 8.1.3 and 10.0-compatible queue tables select count(*), MSG_STATE, QUEUE, CONSUMER_NAME from AQ$<queue_table_name>group by MSG_STATE, QUEUE, CONSUMER_NAME; For multiple-consumer queue tables, if you did not see the expected CONSUMER_NAME , check the syntax of the enqueue code and verify the recipients are declared correctly. If a recipients list is not used on enqueue, check the subscriber list in the AQ$_<queue_table_name>_S view (note that a single-consumer queue table does not have a subscriber view. This view records all members of the default subscription list which were added using the DBMS_AQADM.ADD_SUBSCRIBER procedure and also those enqueued using a recipient list. SQL> select QUEUE, NAME, ADDRESS from AQ$MULTIPLEQTABLE_S;QUEUE NAME ADDRESS---------- ----------- -------------MULTIPLEQ AQUSER2 [email protected] AQUSER1 In this example we have 2 subscribers registered with the queue. We have a local subscriber AQUSER1, and a remote subscriber AQUSER2, on the queue INQ, owned by AQADM, at M2V102.ES. Unless overridden with a recipient list during enqueue every message enqueued to this queue will be propagated to INQ at M2V102.ES.For 8.1 style and above multiple consumer queue tables, you can also check the following information at the target: select CONSUMER_NAME, DEQ_TXN_ID, DEQ_TIME, DEQ_USER_ID, PROPAGATED_MSGID from AQ$<queue_table_name> where QUEUE = '<QUEUE_NAME>'; For 8.0 style queues, if the queue table supports multiple consumers you can obtain the same information from the history column of the queue table: select h.CONSUMER, h.TRANSACTION_ID, h.DEQ_TIME, h.DEQ_USER, h.PROPAGATED_MSGIDfrom AQ$<queue_table_name> t, table(t.history) h where t.Q_NAME = '<QUEUE_NAME>'; A non-NULL TRANSACTION_ID indicates that the message was successfully propagated. Further, the DEQ_TIME indicates the time of propagation, the DEQ_USER indicates the userid used for propagation, and the PROPAGATED_MSGID indicates the message ID of the message that was enqueued at the destination. 6. Additional Troubleshooting Steps for Propagation in an Oracle Streams Environment 6.1. Is the Propagation Enabled? For a propagation job to propagate messages, the propagation must be enabled. For Streams, a special view called DBA_PROPAGATION exists to convey information about Streams propagations. If messages are not being propagated by a propagation as expected, then the propagation might not be enabled. To query for this: SELECT p.PROPAGATION_NAME, DECODE(s.SCHEDULE_DISABLED, 'Y', 'Disabled','N', 'Enabled') SCHEDULE_DISABLED, s.PROCESS_NAME, s.FAILURES, s.LAST_ERROR_MSGFROM DBA_QUEUE_SCHEDULES s, DBA_PROPAGATION pWHERE p.DESTINATION_DBLINK = NVL(REGEXP_SUBSTR(s.DESTINATION, '[^@]+', 1, 2), s.DESTINATION) AND s.SCHEMA = p.SOURCE_QUEUE_OWNER AND s.QNAME = p.SOURCE_QUEUE_NAME AND MESSAGE_DELIVERY_MODE = 'PERSISTENT' order by PROPAGATION_NAME; At times, the propagation job may become "broken" or fail to start after an error has been encountered or after a database restart. If an error is indicated by the above query, an attempt to disable the propagation and then re-enable it can be made. In the examples below, for the propagation named STRMADMIN_PROPAGATE where the queue name is STREAMS_QUEUE owned by STRMADMIN and the destination database link is ORCL2.WORLD, the commands would be:10.2 and above exec dbms_propagation_adm.stop_propagation('STRMADMIN_PROPAGATE'); exec dbms_propagation_adm.start_propagation('STRMADMIN_PROPAGATE'); If the above does not fix the problem, stop the propagation specifying the force parameter (2nd parameter on stop_propagation) as TRUE: exec dbms_propagation_adm.stop_propagation('STRMADMIN_PROPAGATE',true); exec dbms_propagation_adm.start_propagation('STRMADMIN_PROPAGATE'); The statistics for the propagation as well as any old error messages are cleared when the force parameter is set to TRUE. Therefore if the propagation schedule is stopped with FORCE set to TRUE, and upon restart there is still an error message in DBA_PROPAGATION, then the error message is current.9.2 or 10.1 exec dbms_aqadm.disable_propagation_schedule('STRMADMIN.STREAMS_QUEUE','ORCL2.WORLD'); exec dbms.aqadm.enable_propagation_schedule('STRMADMIN.STREAMS_QUEUE','ORCL2.WORLD'); If the above does not fix the problem, perform an unschedule of propagation and then schedule_propagation: exec dbms_aqadm.unschedule_propagation('STRMADMIN.STREAMS_QUEUE','ORCL2.WORLD'); exec dbms_aqadm.schedule_propagation('STRMADMIN.STREAMS_QUEUE','ORCL2.WORLD'); Typically if the error from the first query in Section 6.1 recurs after restarting the propagation as shown above, further troubleshooting of the error is needed. 6.2. Check Propagation Rule Sets and Transformations Inspect the configuration of the rules in the rule set that is associated with the propagation process to make sure that they evaluate to TRUE as expected. If not, then the object or schema will not be propagated. Remember that when a negative rule evaluates to TRUE, the specified object or schema will not be propagated. Finally inspect any rule-based transformations that are implemented with propagation to make sure they are changing the data in the intended way.The following query shows what rule sets are assigned to a propagation: select PROPAGATION_NAME, RULE_SET_OWNER||'.'||RULE_SET_NAME "Positive Rule Set",NEGATIVE_RULE_SET_OWNER||'.'||NEGATIVE_RULE_SET_NAME "Negative Rule Set"from DBA_PROPAGATION; The next two queries list the propagation rules and their conditions. The first is for the positive rule set, the second is for the negative rule set: set long 4000select rsr.RULE_SET_OWNER||'.'||rsr.RULE_SET_NAME RULE_SET ,rsr.RULE_OWNER||'.'||rsr.RULE_NAME RULE_NAME,r.RULE_CONDITION CONDITION fromDBA_RULE_SET_RULES rsr, DBA_RULES rwhere rsr.RULE_NAME = r.RULE_NAME and rsr.RULE_OWNER = r.RULE_OWNER and RULE_SET_NAME in(select RULE_SET_NAME from DBA_PROPAGATION) order by rsr.RULE_SET_OWNER, rsr.RULE_SET_NAME;   set long 4000select c.PROPAGATION_NAME, rsr.RULE_SET_OWNER||'.'||rsr.RULE_SET_NAME RULE_SET ,rsr.RULE_OWNER||'.'||rsr.RULE_NAME RULE_NAME,r.RULE_CONDITION CONDITION fromDBA_RULE_SET_RULES rsr, DBA_RULES r ,DBA_PROPAGATION cwhere rsr.RULE_NAME = r.RULE_NAME and rsr.RULE_OWNER = r.RULE_OWNER andrsr.RULE_SET_OWNER=c.NEGATIVE_RULE_SET_OWNER and rsr.RULE_SET_NAME=c.NEGATIVE_RULE_SET_NAMEand rsr.RULE_SET_NAME in(select NEGATIVE_RULE_SET_NAME from DBA_PROPAGATION) order by rsr.RULE_SET_OWNER, rsr.RULE_SET_NAME; 6.3. Determining the Total Number of Messages and Bytes Propagated As in Section 3.1, determining if messages are flowing can be instructive to see whether the propagation is entirely hung or just slow. If the propagation is not in flow control (see Section 6.5.2), but the statistics are incrementing slowly, there may be a performance issue. For Streams implementations two views are available that can assist with this that can show the number of messages sent by a propagation, as well as the number of acknowledgements being returned from the target site: the V$PROPAGATION_SENDER view at the Source site and the V$PROPAGATION_RECEIVER view at the destination site. It is helpful to query both to determine if messages are being delivered to the target. Look for the statistics to increase.Source: select QUEUE_SCHEMA, QUEUE_NAME, DBLINK,HIGH_WATER_MARK, ACKNOWLEDGEMENT, TOTAL_MSGS, TOTAL_BYTESfrom V$PROPAGATION_SENDER; Target: select SRC_QUEUE_SCHEMA, SRC_QUEUE_NAME, SRC_DBNAME, DST_QUEUE_SCHEMA, DST_QUEUE_NAME, HIGH_WATER_MARK, ACKNOWLEDGEMENT, TOTAL_MSGS from V$PROPAGATION_RECEIVER; 6.4. Check Buffered Subscribers The V$BUFFERED_SUBSCRIBERS view displays information about subscribers for all buffered queues in the instance. This view can be queried to make sure that the site that the propagation is propagating to is listed as a subscriber address for the site being propagated from: select QUEUE_SCHEMA, QUEUE_NAME, SUBSCRIBER_ADDRESS from V$BUFFERED_SUBSCRIBERS; The SUBSCRIBER_ADDRESS column will not be populated when the propagation is local (between queues on the same database). 6.5. Common Streams Propagation Errors 6.5.1. ORA-02082: A loopback database link must have a connection qualifier. This error can occur if you use the Streams Setup Wizard in Oracle Enterprise Manager without first configuring the GLOBAL_NAME for your database. 6.5.2. ORA-25307: Enqueue rate too high. Enable flow control DBA_QUEUE_SCHEDULES will display this informational message for propagation when the automatic flow control (10g feature of Streams) has been invoked.Similar to Streams capture processes, a Streams propagation process can also go into a state of 'flow control. This is an informative message that indicates flow control has been automatically enabled to reduce the rate at which messages are being enqueued into at target queue.This typically occurs when the target site is unable to keep up with the rate of messages flowing from the source site. Other than checking that the apply process is running normally on the target site, usually no action is required by the DBA. Propagation and the capture process will be resumed automatically when the target site is able to accept more messages.The following document contains more information:Document 302109.1 Streams Propagation Error: ORA-25307 Enqueue rate too high. Enable flow controlSee the following document for one potential cause of this situation:Document 1097115.1 Oracle Streams Apply Reader is in 'Paused' State 6.5.3. ORA-25315 unsupported configuration for propagation of buffered messages This error typically occurs when the target database is RAC and usually indicates that an attempt was made to propagate buffered messages with the database link pointing to an instance in the destination database which is not the owner instance of the destination queue. To resolve the problem, use queue-to-queue propagation for buffered messages. 6.5.4. ORA-600 [KWQBMCRCPTS101] after dropping / recreating propagation For cause/fixes refer to:Document 421237.1 ORA-600 [KWQBMCRCPTS101] reported by a Qmon slave process after dropping a Streams Propagation 6.5.5. Stopping or Dropping a Streams Propagation Hangs See the following note:Document 1159787.1 Troubleshooting Streams Propagation When It is Not Functioning and Attempts to Stop It Hang 6.6. Streams Propagation-Related Notes for Common Issues Document 437838.1 Streams Specific PatchesDocument 749181.1 How to Recover Streams After Dropping PropagationDocument 368912.1 Queue to Queue Propagation Schedule encountered ORA-12514 in a RAC environmentDocument 564649.1 ORA-02068/ORA-03114/ORA-03113 Errors From Streams Propagation Process - Remote Database is Available and Unschedule/Reschedule Does Not ResolveDocument 553017.1 Stream Propagation Process Errors Ora-4052 Ora-6554 From 11g To 10201Document 944846.1 Streams Propagation Fails Ora-7445 [kohrsmc]Document 745601.1 ORA-23603 'STREAMS enqueue aborted due to low SGA' Error from Streams Propagation, and V$STREAMS_CAPTURE.STATE Hanging on 'Enqueuing Message'Document 333068.1 ORA-23603: Streams Enqueue Aborted Eue To Low SGADocument 363496.1 Ora-25315 Propagating on RAC StreamsDocument 368237.1 Unable to Unschedule Propagation. Streams Queue is InvalidDocument 436332.1 dbms_propagation_adm.stop_propagation hangsDocument 727389.1 Propagation Fails With ORA-12528Document 730911.1 ORA-4063 Is Reported After Dropping Negative Prop.RulesetDocument 460471.1 Propagation Blocked by Qmon Process - Streams_queue_table / 'library cache lock' waitsDocument 1165583.1 ORA-600 [kwqpuspse0-ack] In Streams EnvironmentDocument 1059029.1 Combined Capture and Apply (CCA) : Capture aborts : ORA-1422 after schedule_propagationDocument 556309.1 Changing Propagation/ queue_to_queue : false -> true does does not work; no LCRs propagatedDocument 839568.1 Propagation failing with error: ORA-01536: space quota exceeded for tablespace ''Document 311021.1 Streams Propagation Process : Ora 12154 After Reboot with Transparent Application Failover TAF configuredDocument 359971.1 STREAMS propagation to Primary of physical Standby configuation errors with Ora-01033, Ora-02068Document 1101616.1 DBMS_PROPAGATION_ADM.DROP_PROPAGATION FAILS WITH ORA-1747 7. Performance Issues A propagation may seem to be slow if the queries from Sections 3.1 and 6.3 show that the message statistics are not changing quickly. In Oracle Streams, this more usually is due to a slow apply process at the target rather than a slow propagation. Propagation could be inferred to be slow if the message statistics are changing, and the state of a capture process according to V$STREAMS_CAPTURE.STATE is PAUSED FOR FLOW CONTROL, but an ORA-25307 'Enqueue rate too high. Enable flow control' warning is NOT observed in DBA_QUEUE_SCHEDULES per Section 6.5.2. If this is the case, see the following notes / white papers for suggestions to increase performance:Document 335516.1 Master Note for Streams Performance RecommendationsDocument 730036.1 Overview for Troubleshooting Streams Performance IssuesDocument 780733.1 Streams Propagation Tuning with Network ParametersWhite Paper: http://www.oracle.com/technetwork/database/features/availability/maa-wp-10gr2-streams-performance-130059.pdfWhite Paper: Oracle Streams Configuration Best Practices: Oracle Database 10g Release 10.2, http://www.oracle.com/technetwork/database/features/availability/maa-10gr2-streams-configuration-132039.pdf, See APPENDIX A: USING STREAMS CONFIGURATIONS OVER A NETWORKFor basic AQ propagation, the network tuning in the aforementioned Appendix A of the white paper 'Oracle Streams Configuration Best Practices: Oracle Database 10g Release 10.2' is applicable. References NOTE:102330.1 - Advanced Queueing MSG_STATE Values and their InterpretationNOTE:102771.1 - Advanced Queueing Propagation using PL/SQLNOTE:1059029.1 - Combined Capture and Apply (CCA) : Capture aborts : ORA-1422 after schedule_propagationNOTE:1079577.1 - Advanced Queuing Propagation Fails With "ORA-22370: incorrect usage of method"NOTE:1083608.1 - 11g Streams and Oracle SchedulerNOTE:1087324.1 - ORA-01405 ORA-01422 reported by Adavanced Queueing Propagation schedules after RAC reconfigurationNOTE:1097115.1 - Oracle Streams Apply Reader is in 'Paused' StateNOTE:1101616.1 - DBMS_PROPAGATION_ADM.DROP_PROPAGATION FAILS WITH ORA-1747NOTE:1159787.1 - Troubleshooting Streams Propagation When It is Not Functioning and Attempts to Stop It HangNOTE:1165583.1 - ORA-600 [kwqpuspse0-ack] In Streams EnvironmentNOTE:118884.1 - How to unschedule a propagation schedule stuck in pending stateNOTE:1203544.1 - AQ PROPAGATION ABORTED WITH ORA-600[OCIKSIN: INVALID STATUS] ON SYS.DBMS_AQADM_SYS.AQ$_PROPAGATION_PROCEDURE AFTER UPGRADENOTE:1204080.1 - AQ Propagation Failing With ORA-25329 After Upgraded From 8i or 9i to 10g or 11g.NOTE:219416.1 - Advanced Queuing Propagation fails with ORA-22922NOTE:222992.1 - DBMS_AQADM.DISABLE_PROPAGATION_SCHEDULE Returns ORA-24082NOTE:253131.1 - Concurrent Writes May Corrupt LOB Segment When Using Auto Segment Space Management (ORA-1555)NOTE:282987.1 - Propagated Messages marked UNDELIVERABLE after Drop and Recreate Of Remote QueueNOTE:298015.1 - Kwqjswproc:Excep After Loop: Assigning To SelfNOTE:302109.1 - Streams Propagation Error: ORA-25307 Enqueue rate too high. Enable flow controlNOTE:311021.1 - Streams Propagation Process : Ora 12154 After Reboot with Transparent Application Failover TAF configuredNOTE:332792.1 - ORA-04061 error relating to SYS.DBMS_PRVTAQIP reported when setting up StatspackNOTE:333068.1 - ORA-23603: Streams Enqueue Aborted Eue To Low SGANOTE:335516.1 - Master Note for Streams Performance RecommendationsNOTE:353325.1 - ORA-24056: Internal inconsistency for QUEUE and destination NOTE:353754.1 - Streams Messaging Propagation Fails between Single and Multi-byte Charactersets when using Chararacter Length Semantics in the ADT.NOTE:359971.1 - STREAMS propagation to Primary of physical Standby configuation errors with Ora-01033, Ora-02068NOTE:363496.1 - Ora-25315 Propagating on RAC StreamsNOTE:365093.1 - ORA-07445 [kwqppay2aqe()+7360] reported on Propagation of a Transformed MessageNOTE:368237.1 - Unable to Unschedule Propagation. Streams Queue is InvalidNOTE:368912.1 - Queue to Queue Propagation Schedule encountered ORA-12514 in a RAC environmentNOTE:421237.1 - ORA-600 [KWQBMCRCPTS101] reported by a Qmon slave process after dropping a Streams PropagationNOTE:436332.1 - dbms_propagation_adm.stop_propagation hangsNOTE:437838.1 - Streams Specific PatchesNOTE:460471.1 - Propagation Blocked by Qmon Process - Streams_queue_table / 'library cache lock' waitsNOTE:463820.1 - Streams Combined Capture and Apply in 11gNOTE:553017.1 - Stream Propagation Process Errors Ora-4052 Ora-6554 From 11g To 10201NOTE:556309.1 - Changing Propagation/ queue_to_queue : false -> true does does not work; no LCRs propagatedNOTE:564649.1 - ORA-02068/ORA-03114/ORA-03113 Errors From Streams Propagation Process - Remote Database is Available and Unschedule/Reschedule Does Not ResolveNOTE:566622.1 - ORA-22275 when propagating >4K AQ$_JMS_TEXT_MESSAGEs from 9.2.0.8 to 10.2.0.1NOTE:727389.1 - Propagation Fails With ORA-12528NOTE:730036.1 - Overview for Troubleshooting Streams Performance IssuesNOTE:730911.1 - ORA-4063 Is Reported After Dropping Negative Prop.RulesetNOTE:731292.1 - ORA-25215 Reported On Local Propagation When Using Transformation with ANYDATA queue tablesNOTE:731539.1 - ORA-29268: HTTP client error 401 Unauthorized Error when the AQ Servlet attempts to Propagate a message via HTTPNOTE:745601.1 - ORA-23603 'STREAMS enqueue aborted due to low SGA' Error from Streams Propagation, and V$STREAMS_CAPTURE.STATE Hanging on 'Enqueuing Message'NOTE:749181.1 - How to Recover Streams After Dropping PropagationNOTE:780733.1 - Streams Propagation Tuning with Network ParametersNOTE:787367.1 - ORA-22275 reported on Propagating Messages with LOB component when propagating between 10.1 and 10.2NOTE:808136.1 - How to clear the old errors from DBA_PROPAGATION view ?NOTE:827184.1 - AQ Propagation with CLOB data types Fails with ORA-22990NOTE:827473.1 - How to alter propagation from queue_to_queue to queue_to_dblinkNOTE:839568.1 - Propagation failing with error: ORA-01536: space quota exceeded for tablespace ''NOTE:846297.1 - AQ Propagation Fails : ORA-00600[kope2upic2954] or Ora-00600[Kghsstream_copyn]NOTE:944846.1 - Streams Propagation Fails Ora-7445 [kohrsmc]

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  • The Beginner’s Guide to Greasemonkey User Scripts in Firefox

    - by Asian Angel
    Everybody knows that Firefox has add-ons for virtually everything, but if you don’t want to bloat your installation you’ve always got the option of Greasemonkey scripts instead. Here’s a quick primer on how to use them. Getting Started with User Scripts Once you have Greasemonkey installed, managing the extension is really easy. Left click on the status bar icon to turn the extension on/off and right click to access the context menu shown here. Whether you use the Options button in the Add-ons Manager Window or the context menu shown above, both will bring up the Manage User Scripts dialog. At the moment you have a nice clean slate to work with… time to get some scripts added in. The majority of user scripts can be found at two different sites, the first being appropriately named userscripts.org, and you can either browse by tag or search for a script. As you can see here your search for a particular type of script can be quickly narrowed down based on category. There is definitely a lot to choose from. For our example we focused on the “textarea” tag. There were 62 scripts available but we quickly found what we were looking for on the first page. Installing, Managing, & Using Your Scripts When you find a script that you want to install visit the script’s homepage and click on the “Install” button. Note: Link for this script provided below. Once you have clicked on the Install button, Greasemonkey will open up the following installation window. You will be able to view: A summary of what the script does A list of websites that the script is supposed to function on (our example is set for all) View the script source if desired Make a final decision on whether to install the script or cancel the process Right-clicking on our status bar icon shows our new script listed and active. Reopening the Manage User Scripts window shows: Our new script listed in the column on the left The websites/pages included An option to disable the script (can also be done in the context menu) The ability to edit the script The ability to uninstall the script If you choose to edit the script you will be asked to browse for and select a default text editor of your choice (first time only). Once you have selected a text editor you can make any changes desired to the script. We decided to test our new user script on the site. Going to the comment box at the bottom we could easily resize the window as desired. The Comment box definitely got a lot bigger. Conclusion If you prefer to keep the number of extensions to a minimum in your Firefox installation then Greasemonkey and the Userscripts website can easily provide that extra functionality without the bloat. For added auto website script detection goodness see our article on Greasefire. Note: See our article here for specialized How-To Geek User Style Scripts that can be added to Greasemonkey. Links Download the Greasemonkey Extension (Mozilla Add-ons) Install the Textarea & Input Resize User Script Visit the Userscripts.org Website Visit the Userstyles.org Website Similar Articles Productive Geek Tips Enjoy How-To Geek User Style Script GoodnessEnable Multi-Column Google Searches with a User ScriptSearch Alternative Search Engines from within Bing’s Search PageFind User Scripts for Your Favorite Websites the Easy WaySet Up User Scripts in Opera Browser TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Office 2010 reviewed in depth by Ed Bott FoxClocks adds World Times in your Statusbar (Firefox) Have Fun Editing Photo Editing with Citrify Outlook Connector Upgrade Error Gadfly is a cool Twitter/Silverlight app Enable DreamScene in Windows 7

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  • Windows Presentation Foundation 4.5 Cookbook Review

    - by Ricardo Peres
    As promised, here’s my review of Windows Presentation Foundation 4.5 Cookbook, that Packt Publishing kindly made available to me. It is an introductory book, targeted at WPF newcomers or users with few experience, following the typical recipes or cookbook style. Like all Packt Publishing books on development, each recipe comes with sample code that is self-sufficient for understanding the concepts it tries to illustrate. It starts on chapter 1 by introducing the most important concepts, the XAML language itself, what can be declared in XAML and how to do it, what are dependency and attached properties as well as markup extensions and events, which should give readers a most required introduction to how WPF works and how to do basic stuff. It moves on to resources on chapter 2, which also makes since, since it’s such an important concept in WPF. Next, chapter 3, come the panels used for laying controls on the screen, all of the out of the box panels are described with typical use cases. Controls come next in chapter 4; the difference between elements and controls is introduced, as well as content controls, headered controls and items controls, and all standard controls are introduced. The book shows how to change the way they look by using templates. The next chapter, 5, talks about top level windows and the WPF application object: how to access startup arguments, how to set the main window, using standard dialogs and there’s even a sample on how to have a irregularly-shaped window. This is one of the most important concepts in WPF: data binding, which is the theme for the following chapter, 6. All common scenarios are introduced, the binding modes, directions, triggers, etc. It talks about the INotifyPropertyChanged interface and how to use it for notifying data binding subscribers of changes in data sources. Data templates and selectors are also covered, as are value converters and data triggers. Examples include master-detail and sorting, grouping and filtering collections and binding trees and grids. Last it covers validation rules and error templates. Chapter 7 talks about the current trend in WPF development, the Model View View-Model (MVVM) framework. This is a well known pattern for connecting things interface to actions, and it is explained competently. A typical implementation is presented which also presents the command pattern used throughout WPF. A complete application using MVVM is presented from start to finish, including typical features such as undo. Style and layout is covered on chapter 8. Why/how to use styles, applying them automatically,  using the many types of triggers to change styles automatically, using Expression Blend behaviors and templates are all covered. Next chapter, 9, is about graphics and animations programming. It explains how to create shapes, transform common UI elements, apply special effects and perform simple animations. The following chapter, 10, is about creating custom controls, either by deriving from UserControl or from an existing control or framework element class, applying custom templates for changing the way the control looks. One useful example is a custom layout panel that arranges its children along a circumference. The final chapter, 11, is about multi-threading programming and how one can integrate it with WPF. Includes how to invoke methods and properties on WPF classes from threads other than the main UI, using background tasks and timers and even using the new C# 5.0 asynchronous operations. It’s an interesting book, like I said, mostly for newcomers. It provides a competent introduction to WPF, with examples that cover the most common scenarios and also give directions to more complex ones. I recommend it to everyone wishing to learn WPF.

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  • Scrum in 5 Minutes

    - by Stephen.Walther
    The goal of this blog entry is to explain the basic concepts of Scrum in less than five minutes. You learn how Scrum can help a team of developers to successfully complete a complex software project. Product Backlog and the Product Owner Imagine that you are part of a team which needs to create a new website – for example, an e-commerce website. You have an overwhelming amount of work to do. You need to build (or possibly buy) a shopping cart, install an SSL certificate, create a product catalog, create a Facebook page, and at least a hundred other things that you have not thought of yet. According to Scrum, the first thing you should do is create a list. Place the highest priority items at the top of the list and the lower priority items lower in the list. For example, creating the shopping cart and buying the domain name might be high priority items and creating a Facebook page might be a lower priority item. In Scrum, this list is called the Product Backlog. How do you prioritize the items in the Product Backlog? Different stakeholders in the project might have different priorities. Gary, your division VP, thinks that it is crucial that the e-commerce site has a mobile app. Sally, your direct manager, thinks taking advantage of new HTML5 features is much more important. Multiple people are pulling you in different directions. According to Scrum, it is important that you always designate one person, and only one person, as the Product Owner. The Product Owner is the person who decides what items should be added to the Product Backlog and the priority of the items in the Product Backlog. The Product Owner could be the customer who is paying the bills, the project manager who is responsible for delivering the project, or a customer representative. The critical point is that the Product Owner must always be a single person and that single person has absolute authority over the Product Backlog. Sprints and the Sprint Backlog So now the developer team has a prioritized list of items and they can start work. The team starts implementing the first item in the Backlog — the shopping cart — and the team is making good progress. Unfortunately, however, half-way through the work of implementing the shopping cart, the Product Owner changes his mind. The Product Owner decides that it is much more important to create the product catalog before the shopping cart. With some frustration, the team switches their developmental efforts to focus on implementing the product catalog. However, part way through completing this work, once again the Product Owner changes his mind about the highest priority item. Getting work done when priorities are constantly shifting is frustrating for the developer team and it results in lower productivity. At the same time, however, the Product Owner needs to have absolute authority over the priority of the items which need to get done. Scrum solves this conflict with the concept of Sprints. In Scrum, a developer team works in Sprints. At the beginning of a Sprint the developers and the Product Owner agree on the items from the backlog which they will complete during the Sprint. This subset of items from the Product Backlog becomes the Sprint Backlog. During the Sprint, the Product Owner is not allowed to change the items in the Sprint Backlog. In other words, the Product Owner cannot shift priorities on the developer team during the Sprint. Different teams use Sprints of different lengths such as one month Sprints, two-week Sprints, and one week Sprints. For high-stress, time critical projects, teams typically choose shorter sprints such as one week sprints. For more mature projects, longer one month sprints might be more appropriate. A team can pick whatever Sprint length makes sense for them just as long as the team is consistent. You should pick a Sprint length and stick with it. Daily Scrum During a Sprint, the developer team needs to have meetings to coordinate their work on completing the items in the Sprint Backlog. For example, the team needs to discuss who is working on what and whether any blocking issues have been discovered. Developers hate meetings (well, sane developers hate meetings). Meetings take developers away from their work of actually implementing stuff as opposed to talking about implementing stuff. However, a developer team which never has meetings and never coordinates their work also has problems. For example, Fred might get stuck on a programming problem for days and never reach out for help even though Tom (who sits in the cubicle next to him) has already solved the very same problem. Or, both Ted and Fred might have started working on the same item from the Sprint Backlog at the same time. In Scrum, these conflicting needs – limiting meetings but enabling team coordination – are resolved with the idea of the Daily Scrum. The Daily Scrum is a meeting for coordinating the work of the developer team which happens once a day. To keep the meeting short, each developer answers only the following three questions: 1. What have you done since yesterday? 2. What do you plan to do today? 3. Any impediments in your way? During the Daily Scrum, developers are not allowed to talk about issues with their cat, do demos of their latest work, or tell heroic stories of programming problems overcome. The meeting must be kept short — typically about 15 minutes. Issues which come up during the Daily Scrum should be discussed in separate meetings which do not involve the whole developer team. Stories and Tasks Items in the Product or Sprint Backlog – such as building a shopping cart or creating a Facebook page – are often referred to as User Stories or Stories. The Stories are created by the Product Owner and should represent some business need. Unlike the Product Owner, the developer team needs to think about how a Story should be implemented. At the beginning of a Sprint, the developer team takes the Stories from the Sprint Backlog and breaks the stories into tasks. For example, the developer team might take the Create a Shopping Cart story and break it into the following tasks: · Enable users to add and remote items from shopping cart · Persist the shopping cart to database between visits · Redirect user to checkout page when Checkout button is clicked During the Daily Scrum, members of the developer team volunteer to complete the tasks required to implement the next Story in the Sprint Backlog. When a developer talks about what he did yesterday or plans to do tomorrow then the developer should be referring to a task. Stories are owned by the Product Owner and a story is all about business value. In contrast, the tasks are owned by the developer team and a task is all about implementation details. A story might take several days or weeks to complete. A task is something which a developer can complete in less than a day. Some teams get lazy about breaking stories into tasks. Neglecting to break stories into tasks can lead to “Never Ending Stories” If you don’t break a story into tasks, then you can’t know how much of a story has actually been completed because you don’t have a clear idea about the implementation steps required to complete the story. Scrumboard During the Daily Scrum, the developer team uses a Scrumboard to coordinate their work. A Scrumboard contains a list of the stories for the current Sprint, the tasks associated with each Story, and the state of each task. The developer team uses the Scrumboard so everyone on the team can see, at a glance, what everyone is working on. As a developer works on a task, the task moves from state to state and the state of the task is updated on the Scrumboard. Common task states are ToDo, In Progress, and Done. Some teams include additional task states such as Needs Review or Needs Testing. Some teams use a physical Scrumboard. In that case, you use index cards to represent the stories and the tasks and you tack the index cards onto a physical board. Using a physical Scrumboard has several disadvantages. A physical Scrumboard does not work well with a distributed team – for example, it is hard to share the same physical Scrumboard between Boston and Seattle. Also, generating reports from a physical Scrumboard is more difficult than generating reports from an online Scrumboard. Estimating Stories and Tasks Stakeholders in a project, the people investing in a project, need to have an idea of how a project is progressing and when the project will be completed. For example, if you are investing in creating an e-commerce site, you need to know when the site can be launched. It is not enough to just say that “the project will be done when it is done” because the stakeholders almost certainly have a limited budget to devote to the project. The people investing in the project cannot determine the business value of the project unless they can have an estimate of how long it will take to complete the project. Developers hate to give estimates. The reason that developers hate to give estimates is that the estimates are almost always completely made up. For example, you really don’t know how long it takes to build a shopping cart until you finish building a shopping cart, and at that point, the estimate is no longer useful. The problem is that writing code is much more like Finding a Cure for Cancer than Building a Brick Wall. Building a brick wall is very straightforward. After you learn how to add one brick to a wall, you understand everything that is involved in adding a brick to a wall. There is no additional research required and no surprises. If, on the other hand, I assembled a team of scientists and asked them to find a cure for cancer, and estimate exactly how long it will take, they would have no idea. The problem is that there are too many unknowns. I don’t know how to cure cancer, I need to do a lot of research here, so I cannot even begin to estimate how long it will take. So developers hate to provide estimates, but the Product Owner and other product stakeholders, have a legitimate need for estimates. Scrum resolves this conflict by using the idea of Story Points. Different teams use different units to represent Story Points. For example, some teams use shirt sizes such as Small, Medium, Large, and X-Large. Some teams prefer to use Coffee Cup sizes such as Tall, Short, and Grande. Finally, some teams like to use numbers from the Fibonacci series. These alternative units are converted into a Story Point value. Regardless of the type of unit which you use to represent Story Points, the goal is the same. Instead of attempting to estimate a Story in hours (which is doomed to failure), you use a much less fine-grained measure of work. A developer team is much more likely to be able to estimate that a Story is Small or X-Large than the exact number of hours required to complete the story. So you can think of Story Points as a compromise between the needs of the Product Owner and the developer team. When a Sprint starts, the developer team devotes more time to thinking about the Stories in a Sprint and the developer team breaks the Stories into Tasks. In Scrum, you estimate the work required to complete a Story by using Story Points and you estimate the work required to complete a task by using hours. The difference between Stories and Tasks is that you don’t create a task until you are just about ready to start working on a task. A task is something that you should be able to create within a day, so you have a much better chance of providing an accurate estimate of the work required to complete a task than a story. Burndown Charts In Scrum, you use Burndown charts to represent the remaining work on a project. You use Release Burndown charts to represent the overall remaining work for a project and you use Sprint Burndown charts to represent the overall remaining work for a particular Sprint. You create a Release Burndown chart by calculating the remaining number of uncompleted Story Points for the entire Product Backlog every day. The vertical axis represents Story Points and the horizontal axis represents time. A Sprint Burndown chart is similar to a Release Burndown chart, but it focuses on the remaining work for a particular Sprint. There are two different types of Sprint Burndown charts. You can either represent the remaining work in a Sprint with Story Points or with task hours (the following image, taken from Wikipedia, uses hours). When each Product Backlog Story is completed, the Release Burndown chart slopes down. When each Story or task is completed, the Sprint Burndown chart slopes down. Burndown charts typically do not always slope down over time. As new work is added to the Product Backlog, the Release Burndown chart slopes up. If new tasks are discovered during a Sprint, the Sprint Burndown chart will also slope up. The purpose of a Burndown chart is to give you a way to track team progress over time. If, halfway through a Sprint, the Sprint Burndown chart is still climbing a hill then you know that you are in trouble. Team Velocity Stakeholders in a project always want more work done faster. For example, the Product Owner for the e-commerce site wants the website to launch before tomorrow. Developers tend to be overly optimistic. Rarely do developers acknowledge the physical limitations of reality. So Project stakeholders and the developer team often collude to delude themselves about how much work can be done and how quickly. Too many software projects begin in a state of optimism and end in frustration as deadlines zoom by. In Scrum, this problem is overcome by calculating a number called the Team Velocity. The Team Velocity is a measure of the average number of Story Points which a team has completed in previous Sprints. Knowing the Team Velocity is important during the Sprint Planning meeting when the Product Owner and the developer team work together to determine the number of stories which can be completed in the next Sprint. If you know the Team Velocity then you can avoid committing to do more work than the team has been able to accomplish in the past, and your team is much more likely to complete all of the work required for the next Sprint. Scrum Master There are three roles in Scrum: the Product Owner, the developer team, and the Scrum Master. I’v e already discussed the Product Owner. The Product Owner is the one and only person who maintains the Product Backlog and prioritizes the stories. I’ve also described the role of the developer team. The members of the developer team do the work of implementing the stories by breaking the stories into tasks. The final role, which I have not discussed, is the role of the Scrum Master. The Scrum Master is responsible for ensuring that the team is following the Scrum process. For example, the Scrum Master is responsible for making sure that there is a Daily Scrum meeting and that everyone answers the standard three questions. The Scrum Master is also responsible for removing (non-technical) impediments which the team might encounter. For example, if the team cannot start work until everyone installs the latest version of Microsoft Visual Studio then the Scrum Master has the responsibility of working with management to get the latest version of Visual Studio as quickly as possible. The Scrum Master can be a member of the developer team. Furthermore, different people can take on the role of the Scrum Master over time. The Scrum Master, however, cannot be the same person as the Product Owner. Using SonicAgile SonicAgile (SonicAgile.com) is an online tool which you can use to manage your projects using Scrum. You can use the SonicAgile Product Backlog to create a prioritized list of stories. You can estimate the size of the Stories using different Story Point units such as Shirt Sizes and Coffee Cup sizes. You can use SonicAgile during the Sprint Planning meeting to select the Stories that you want to complete during a particular Sprint. You can configure Sprints to be any length of time. SonicAgile calculates Team Velocity automatically and displays a warning when you add too many stories to a Sprint. In other words, it warns you when it thinks you are overcommitting in a Sprint. SonicAgile also includes a Scrumboard which displays the list of Stories selected for a Sprint and the tasks associated with each story. You can drag tasks from one task state to another. Finally, SonicAgile enables you to generate Release Burndown and Sprint Burndown charts. You can use these charts to view the progress of your team. To learn more about SonicAgile, visit SonicAgile.com. Summary In this post, I described many of the basic concepts of Scrum. You learned how a Product Owner uses a Product Backlog to create a prioritized list of tasks. I explained why work is completed in Sprints so the developer team can be more productive. I also explained how a developer team uses the daily scrum to coordinate their work. You learned how the developer team uses a Scrumboard to see, at a glance, who is working on what and the state of each task. I also discussed Burndown charts. You learned how you can use both Release and Sprint Burndown charts to track team progress in completing a project. Finally, I described the crucial role of the Scrum Master – the person who is responsible for ensuring that the rules of Scrum are being followed. My goal was not to describe all of the concepts of Scrum. This post was intended to be an introductory overview. For a comprehensive explanation of Scrum, I recommend reading Ken Schwaber’s book Agile Project Management with Scrum: http://www.amazon.com/Agile-Project-Management-Microsoft-Professional/dp/073561993X/ref=la_B001H6ODMC_1_1?ie=UTF8&qid=1345224000&sr=1-1

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  • Installer Reboots at "Detecting hardware" (disks and other hardware) on all recent Server Installs

    - by Ryan Rosario
    I have a very frustrating problem with my PC. I cannot install any recent version of Ubuntu Server (or even Desktop) since 9.04 even using the text-based installer. I boot from a USB stick created by Unetbootin (I also tried other methods such as startup disk creator with no difference). On the Server installer, it gets to "Detecting Hardware" (the second one about disks and all other hardware, not network hardware) and then either hangs at 0% (waited 24 hours), or reboots after a minute or two. My system (late 2007): ASUS P5NSLI motherboard Intel Core 2 Duo E6600 2.4Ghz 2 x 1GB Corsair 667MHz RAM nVidia GeForce 6600 I have unplugged everything (including the only hard disk, CD-ROMs and floppy). I have only one stick of RAM (tried each one to no avail) and am booting the installer from a USB stick (booting from CD-ROM yields the same problem). I also tried several of the boot options (nomodeset, nousb, acpi=off, noapic, i915.modeset=1/0, xforcevesa) in all combinations) to no avail. The only active parts of my system are the video card, mouse, keyboard and USB stick. I have also updated the BIOS to the most recent version. (FWIW, on the Desktop installer, I get a black screen after hitting the Install option.) Even after removing "quiet" I am unable to see what kernel panic is occurring (or not occurring) to cause the install to crash. I am only able to save the debug logs via a simple webserver in the installer. After the last line (I repeatedly refreshed), the server stops responding and the installer hangs or reboots: Jan 2 01:04:03 main-menu[302]: INFO: Menu item 'disk-detect' selected Jan 2 01:04:04 kernel: [ 309.154372] sata_nv 0000:00:0e.0: version 3.5 Jan 2 01:04:04 kernel: [ 309.154409] sata_nv 0000:00:0e.0: Using SWNCQ mode Jan 2 01:04:04 kernel: [ 309.154531] sata_nv 0000:00:0e.0: setting latency timer to 64 Jan 2 01:04:04 kernel: [ 309.164442] scsi0 : sata_nv Jan 2 01:04:04 kernel: [ 309.167610] scsi1 : sata_nv Jan 2 01:04:04 kernel: [ 309.167762] ata1: SATA max UDMA/133 cmd 0x9f0 ctl 0xbf0 bmdma 0xd400 irq 10 Jan 2 01:04:04 kernel: [ 309.167774] ata2: SATA max UDMA/133 cmd 0x970 ctl 0xb70 bmdma 0xd408 irq 10 Jan 2 01:04:04 kernel: [ 309.167948] sata_nv 0000:00:0f.0: Using SWNCQ mode Jan 2 01:04:04 kernel: [ 309.168071] sata_nv 0000:00:0f.0: setting latency timer to 64 Jan 2 01:04:04 kernel: [ 309.171931] scsi2 : sata_nv Jan 2 01:04:04 kernel: [ 309.173793] scsi3 : sata_nv Jan 2 01:04:04 kernel: [ 309.173943] ata3: SATA max UDMA/133 cmd 0x9e0 ctl 0xbe0 bmdma 0xe800 irq 11 Jan 2 01:04:04 kernel: [ 309.173954] ata4: SATA max UDMA/133 cmd 0x960 ctl 0xb60 bmdma 0xe808 irq 11 Jan 2 01:04:04 kernel: [ 309.174061] pata_amd 0000:00:0d.0: version 0.4.1 Jan 2 01:04:04 kernel: [ 309.174160] pata_amd 0000:00:0d.0: setting latency timer to 64 Jan 2 01:04:04 kernel: [ 309.177045] scsi4 : pata_amd Jan 2 01:04:04 kernel: [ 309.178628] scsi5 : pata_amd Jan 2 01:04:04 kernel: [ 309.178801] ata5: PATA max UDMA/133 cmd 0x1f0 ctl 0x3f6 bmdma 0xf000 irq 14 Jan 2 01:04:04 kernel: [ 309.178811] ata6: PATA max UDMA/133 cmd 0x170 ctl 0x376 bmdma 0xf008 irq 15 Jan 2 01:04:04 net/hw-detect.hotplug: Detected hotpluggable network interface eth0 Jan 2 01:04:04 net/hw-detect.hotplug: Detected hotpluggable network interface lo Jan 2 01:04:04 kernel: [ 309.485062] ata3: SATA link down (SStatus 0 SControl 300) Jan 2 01:04:04 kernel: [ 309.633094] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) Jan 2 01:04:04 kernel: [ 309.641647] ata1.00: ATA-8: ST31000528AS, CC38, max UDMA/133 Jan 2 01:04:04 kernel: [ 309.641658] ata1.00: 1953525168 sectors, multi 1: LBA48 NCQ (depth 31/32) Jan 2 01:04:04 kernel: [ 309.657614] ata1.00: configured for UDMA/133 Jan 2 01:04:04 kernel: [ 309.657969] scsi 0:0:0:0: Direct-Access ATA ST31000528AS CC38 PQ: 0 ANSI: 5 Jan 2 01:04:04 kernel: [ 309.658482] sd 0:0:0:0: Attached scsi generic sg0 type 0 Jan 2 01:04:04 kernel: [ 309.658588] sd 0:0:0:0: [sda] 1953525168 512-byte logical blocks: (1.00 TB/931 GiB) Jan 2 01:04:04 kernel: [ 309.658812] sd 0:0:0:0: [sda] Write Protect is off Jan 2 01:04:04 kernel: [ 309.658823] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00 Jan 2 01:04:04 kernel: [ 309.658918] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA Jan 2 01:04:04 kernel: [ 309.675630] sda: sda1 sda2 Jan 2 01:04:04 kernel: [ 309.676440] sd 0:0:0:0: [sda] Attached SCSI disk Jan 2 01:04:05 kernel: [ 309.969102] ata2: SATA link down (SStatus 0 SControl 300) Jan 2 01:04:05 kernel: [ 310.281137] ata4: SATA link down (SStatus 0 SControl 300) Anybody have any additional ideas I could try? I am getting ready to just toss the motherboard.

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  • Are you cashing in on the MVP complimentary subscriptions ?

    - by Tarun Arora
    The two most asked questions in the Microsoft technology communities around the Microsoft MVP program are, 1. How do I become a Microsoft MVP? 2. What benefits do I get as an MVP? The answer to the first question has been well answered here. In this blog post, I’ll try and answer the second question.           Please find a comprehensive list of Not for Resale personal subscriptions of various products that Microsoft MVP’s are eligible for Product Description Details JetBrains Resharper, dotTrace, dotCover & WebStorm  https://www.jetbrains.com/resharper/buy/mvp.html RedGate Sql server development, database administration, .net development, azure development (merged with Cerebrata), mySQL development, Oracle development http://www.red-gate.com/community/mvp-program Pluralsight Pluralsight on demand training http://blog.pluralsight.com/2011/02/28/pluralsight-for-mvp/ Cerebrata Cloud storage studio and Azure Diagnostic Manager (part of redgate now) https://www.cerebrata.com/Offers/mvp.aspx Telerik Telerik Ultimate collection & Telerik TeamPulse http://blogs.telerik.com/blogs/posts/11-03-01/telerik-gift-for-microsoft-mvps.aspx Developer Express DevEx controls http://www.devexpress.com/Home/Community/mvp.xml InnerWorking 600 hours of .net training catalogue http://www.innerworkings.com/mvp Typemock Typemock Isolator, Typemock Isolator for Sharepoint developers, Typemock Isolator for web developers, TestDriven.NET http://www.typemock.com/mvp SpeakFlow A suite of tools for creating, managing, and delivering non-linear presentations http://www.speakflow.com/ TechSmith Camtasia Studio, SnagIt, screen cast http://www.techsmith.com/camtasia.html Altova Altova XML spy http://www.altova.com/xml-editor/ Visual SVN VisualSVN Subversion integration plug-in for Visual Studio http://www.visualsvn.com/visualsvn/purchase/mvp/ PreEmptive Solution Professional PreEmptive Analytics, Dotfuscator http://www.preemptive.com/landing/mvp Armadillo Armadillo Adaptive Bug Prevention http://www.armadilloverdrive.com/ IS Decisions NFR license to Userlock, RemoteExec, FileAudit & WinReporter http://www.isdecisions.com/download/mvp-mct-program.htm Idera SQL tools http://www.idera.com/Content/Home.aspx West Wind Help Builder Help builder solution http://www.west-wind.com/weblog/posts/2005/Mar/09/Are-you-a-Microsoft-MVP-Get-a-FREE-copy-of-West-Wind-Html-Help-Builder Bamboo Sharepoint tools http://community.bamboosolutions.com/blogs/partner-advantage-program/archive/2008/08/01/partner-advantage-program-mvp.aspx Nitriq Nitriq code analysis http://blog.nitriq.com/FreeLicensesForMicrosoftMVPs.aspx ByteScout Components, Libraries and Developer Tools http://bytescout.com/buy/purchase_nfr_for_mvp.html YourKit Java and .net Profiler http://yourkit.com/.net/profiler/index.jsp Aspose .NET components http://www.aspose.com/corporate/community/2012_05_08_nfr-licenses-for-community-leaders.aspx Apart from google bing fu; stackoverflow and breathtech were a great help in compiling the above list. If you know of any other benefits, offers or complimentary subscriptions on offer for MVPs not cover in the list above, please add to the comment thread and I’ll have it updated in the list. Enjoy

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  • Lost all privileges since upgrading to 13.10

    - by Chris Poole
    Since upgrading to 13.10, I no longer have the 'privileges' to do the following things: Mount USB/CDROM drives Run software centre or software updater Press the GUI shut down or restart buttons Unlock my account in the 'settings - user accounts' section (padlock is greyed out) Also, when logging on as a guest user I get error messages relating to Compiz crashing with SIGSEGV and it hangs on a blank wallpaper screen. However, I still am able to use sudo in the terminal. Output of 'groups' is jenchris adm dialout cdrom sudo audio video plugdev lpadmin admin pulse pulse-access sambashare sudo usermod -U username doesn't have any effect Output of sudo dpkg-reconfigure -phigh -a acpid stop/waiting acpid start/running, process 30454 * Starting AppArmor profiles Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd [ OK ] * Reloading AppArmor profiles Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox Skipping profile in /etc/apparmor.d/disable: usr.sbin.rsyslogd [ OK ] apport stop/waiting apport start/running gpg: key 437D05B5: "Ubuntu Archive Automatic Signing Key <[email protected]>" not changed gpg: key FBB75451: "Ubuntu CD Image Automatic Signing Key <[email protected]>" not changed gpg: key C0B21F32: "Ubuntu Archive Automatic Signing Key (2012) <[email protected]>" not changed gpg: key EFE21092: "Ubuntu CD Image Automatic Signing Key (2012) <[email protected]>" not changed gpg: Total number processed: 4 gpg: unchanged: 4 atd stop/waiting atd start/running, process 1388 avahi-daemon stop/waiting avahi-daemon start/running, process 1521 Rebuilding /usr/share/applications/bamf-2.index... update-alternatives: using /usr/share/man/man7/bash-builtins.7.gz to provide /usr/share/man/man7/builtins.7.gz (builtins.7.gz) in auto mode update-binfmts: warning: current package is openjdk-7, but binary format already installed by openjdk-6 binfmt-support stop/waiting bluetooth stop/waiting bluetooth start/running, process 4255 update-initramfs: deferring update (trigger activated) /var/lib/dpkg/info/compiz.config: 1: /var/lib/dpkg/info/compiz.config: [general]: not found /var/lib/dpkg/info/compiz.config: 2: /var/lib/dpkg/info/compiz.config: backend: not found /var/lib/dpkg/info/compiz.config: 3: /var/lib/dpkg/info/compiz.config: plugin_list_autosort: not found /var/lib/dpkg/info/compiz.config: 5: /var/lib/dpkg/info/compiz.config: [gnome_session]: not found /var/lib/dpkg/info/compiz.config: 6: /var/lib/dpkg/info/compiz.config: backend: not found /var/lib/dpkg/info/compiz.config: 7: /var/lib/dpkg/info/compiz.config: integration: not found /var/lib/dpkg/info/compiz.config: 8: /var/lib/dpkg/info/compiz.config: plugin_list_autosort: not found /var/lib/dpkg/info/compiz.config: 9: /var/lib/dpkg/info/compiz.config: profile: not found /var/lib/dpkg/info/compiz.config: 11: /var/lib/dpkg/info/compiz.config: [general_ubuntu]: not found /var/lib/dpkg/info/compiz.config: 12: /var/lib/dpkg/info/compiz.config: backend: not found /var/lib/dpkg/info/compiz.config: 13: /var/lib/dpkg/info/compiz.config: integration: not found /var/lib/dpkg/info/compiz.config: 14: /var/lib/dpkg/info/compiz.config: plugin_list_autosort: not found /var/lib/dpkg/info/compiz.config: 15: /var/lib/dpkg/info/compiz.config: profile: not found

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