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  • Calculated Fields - Idiosyncracies

    - by PointsToShare
    © 2011 By: Dov Trietsch. All rights reserved Calculated Fields and some of their Idiosyncrasies Did you try to write a calculate field formula directly into the screen? Good Luck – You’ll need it! Calculated Fields are a sophisticated OOB feature of SharePoint, so you could think that they are best left to the end users – at least to the power users. But they reach their limits before the “Professionals “do, and the tough ones come back to us anyway. Back to business; the simpler the formula, the easier it is. Still, use your favorite editor to write it, then cut it and paste it to the ridiculously small window. What about complex formulae? Write them in steps! Here is a case in point and an idiosyncrasy or two. Our welders need to be certified and recertified every two years. Some of them are certifiable…., but I digress. To be certified you need to pass an eye exam, and two more tests – test A and test B. for each of those you have an expiry date. When renewed, each expiry date is advanced by two years from the date of renewal. My users wanted a visual clue so that when the supervisor looks at the list, she’ll have a KPI symbol telling her if anything expired (Red), is going to expire within the next 90 days (Yellow) or is not to be worried about (green). Not all the dates are filled and any blank date implies a complete lack of certification in the particular requirement. Obviously, I needed to figure the minimal of these 3 dates – a simple enough formula: =MIN([Date_EyeExam], {Date_TestA], [Date_TestB]). Aha! Here is idiosyncrasy #1. When one of the dates is a null, MIN(Date1, Date2) returns the non null date. Null is construed as “Far, far away”. The funny thing is that when you compare it to Today, the null is the lesser one. So a null it is less than today, but not when MIN is calculated. Now, to me the fact that the welder does not have an exam date, is synonymous with his exam being prehistoric, or at least past due. So here is what I did: Solution: Let’s set a blank date to 1/1/1800. How will we do that? Use the IF. IF([Field] rel relValue, TrueValue, FalseValue). rel is any relationship operator <, >, <=, >=, =, <>. If the field is related to the relValue as prescribed, the “IF” returns the TrueValue, otherwise it returns the FalseValue. Thus: =IF([SomeDate]="",1/1/1800,[SomeDate]) will return 1/1/1800 if the date is blank and the date itself if not. So, using this formula, if the welder missed an exam, the returned exam date will be far in the past. It would be nice if we could take such a formula and make it into a reusable function. Alas, here is a calculated field serious shortcoming: You cannot write subs and functions!! Aha, but we can use interim calculated fields! So let’s create 3 calculated fields as follows: 1: c_DateTestA as a calculated field of the date type, with the formula:  IF([Date_TestA]="",1/1/1800,[Date_TestA]) 2: c_DateTestB as a calculated field of the date type, with the formula:  IF([Date_TestB]="",1/1/1800,[Date_TestB]) 3: c_DateEyeExam as a calculated field of the date type, with the formula:  IF([Date_EyeExam]="",1/1/1800,[Date_EyeExam]) And now use these to get c_MinDate. This is again a calculated field of type date with the formula: MIN(c_DateTestA, cDateTestB, c_DateEyeExam) Note that I missed the square parentheses. In “properly named fields – where there are no embedded spaces, we don’t need the square parentheses. I actually strongly recommend using underscores in place of spaces in all the field names in your lists. Among other things, it makes using CAML much simpler. Now, we still need to apply the KPI to this minimal date. I am going to use the available KPI graphics that come with SharePoint and are always available in your 12 hive. "/_layouts/images/kpidefault-2.gif" is the Red KPI "/_layouts/images/kpidefault-1.gif" is the Yellow KPI "/_layouts/images/kpidefault-0.gif" is the Green KPI And here is the nested IF formula that will do the trick: =IF(c_MinDate<=Today,"/_layouts/images/kpidefault-2.gif", IF(cMinDate<Today+90,"/_layouts/images/kpidefault-1.gif","/_layouts/images/kpidefault-0.gif")) Nice! BUT when I tested, it did not work! This is Idiosyncrasy #2: A calculated field based on a calculated field based on a calculated field does not work. You have to stop at two levels! Back to the drawing board: We have to reduce by one level. How? We’ll eliminate the c_DateX items in the formula and replace them with the proper IF formulae. Notice that this needs to be done with precision. You are much better off in doing it in your favorite line editor, than inside the cramped space that SharePoint gives you. So here is the result: MIN(IF([Date_TestA]="",1/1/1800,[ Date_TestA]), IF([Date_TestB]="",1/1/1800,[ Date_TestB]), 1/1/1800), IF([Date_EyeExam]="",1/1/1800,[Date_EyeExam])) Note that I bolded the parentheses and painted them red. They have to match for this formula to work. Now we can leave the KPI formula as is and test again. This time with SUCCESS! Conclusion: build the inner functions first, and then embed them inside the outer formulae. Do this as long as necessary. Use your favorite line editor. Limit yourself to 2 levels. That’s all folks! Almost! As soon as I finished doing all of the above, my users added yet another level of complexity. They added another test, a test that must be passed, but never expires and asked for yet another KPI, this time in Black to denote that any test is not just past due, but altogether missing. I just finished this. Let’s hope it ends here! And OH, the formula  =IF(c_MinDate<=Today,"/_layouts/images/kpidefault-2.gif",IF(cMinDate<Today+90,"/_layouts/images/kpidefault-1.gif","/_layouts/images/kpidefault-0.gif")) Deals with “Today” and this is a subject deserving a discussion of its own!  That’s all folks?! (and this time I mean it)

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  • REL ME tag - trying to figure it out

    - by nekdo
    Regarding http://support.google.com/webmasters/bin/answer.py?hl=en&answer=1229920 to scrolled down section ''Examples'' to the point ''1.'' to the second code line which is: <a rel="me" href="https://plus.google.com/105240469625818678725/"> <img src="//www.google.com/images/icons/ui/gprofile_button-16.png"></a> On the page says that I have to add this line to the Contact Me page of own website in order to get Google Profile button. Exact code which one should be copy and pasted I am able to get here: http://www.google.com/webmasters/profilebutton/ Questions: 1). As you can see on the second URL, to make Google Profile button I need to use "author" tag and not "me" tag. But the first URL which I showed (the line in this message above) shows that I have to use "me" tag and even without this: width="32" height="32". I am already aware that I have to type (second URL) my own Google Profile URL. So do I just MANUALLY ( ! ) change this: <a rel="author" href="https://profiles.google.com/109412257237874861202"> <img src="http://www.google.com/images/icons/ui/gprofile_button-32.png" width="32" height="32"></a> to this (note: two changes done): <a rel="me" href="https://profiles.google.com/109412257237874861202"> <img src="http://www.google.com/images/icons/ui/gprofile_button-32.png"></a> Is this correct? I assume that plus.google.com is the same as profiles.google.com (both is URL of Google Profile). 2). If I was wrong with my first question then the second answer probably won't be even useful but still: Where exactly should I paste the code: <a rel="me" href="https://profiles.google.com/109412257237874861202"> <img src="http://www.google.com/images/icons/ui/gprofile_button-32.png"></a> inside Author Page of own website? I think it doesn't matter where. Also: will this icon be for sure enough or do I also have to make such anchor text with rel me in a ''shape'' of text (for word sentence such as ''Look At My Google Profile'')? Or is just icon really enough? 3). In the same section (''1.'') of the same page (link [first one] provided above) it says that I need to use first author tag to link to Author/Contact Me page of own website in order to later use Me tag. But I think in the explanation is little mistake. Shouldn't be instead of: <a rel="author" href="http://www.cnet.com/profile/iamjaygreene/">Jay Greene</a> this: <a rel="author" href="http://www.cnet.com/profile/iamjaygreene.html">Jay Greene</a> ?

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  • Permanently Sync a wiimote with a computer

    - by Adam Geisweit
    i have tried to look up many ways to sync up my wiimotes to my computer so that i can program games with it, but every time it only syncs them up temporarily, or if it says it can permanently sync it, it doesn't actually do it. it gets tiresome when i have to keep on reconnecting it every time i want to save battery life. how would i be able to sync up my wiimote to my computer so that if i turn off my wiimote, i can just hit any button and it will automatically sync it up?

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  • Installing Microsoft Atlanta

    - by John Paul Cook
    Since my previous post on Microsoft Atlanta, I've been asked how someone can get started with it. Go to https://www.microsoftatlanta.com/ and click the Create Account button using a Windows Live id such as a Hotmail account. If you don’t have Silverlight installed, you’ll be prompted to install it somewhere along the way. I encourage you to install Atlanta and try it out. The product is still being developed and your early feedback can make a difference. When you click Download Registration Certificate...(read more)

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  • How do you track display impressions in Google Analytics on non Google networks?

    - by dee
    Google Analytics has a Multi-Channel funnel analysis feature that we’d like to use to understand assisted conversions and how each channel has impacted on conversion beyond just last interaction attribution. My current understanding is that the impression tracking part of this feature works really well when playing within Google’s search and display networks. Outside of Google’s network I suspect that impression tracking will no longer “just work” and feed back into GA appropriately. What our options are for tracking display impressions on other advertising networks so that we can be attributing value correctly with GA?

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  • Friday Fun: Let The Bullets Fly 2

    - by Asian Angel
    Friday is finally here again, so take a few minutes to relax and have some fun! In this week’s game you are a pistol carrying sharp-shooter with a mission to eliminate the legion of evil henchmen scattered across different locations. Do you have the skill and patience needed to defeat them? How To Properly Scan a Photograph (And Get An Even Better Image) The HTG Guide to Hiding Your Data in a TrueCrypt Hidden Volume Make Your Own Windows 8 Start Button with Zero Memory Usage

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  • Ugly right-click menu and menubar in some applications

    - by halflings
    After installing some packages (unfortunately I can't remember which ones) and installing some GTK3 themes (Faience / Faenza), my terminal's menubar and the right-click menu (in some contexts) started to look very ugly ! 1: Right-click menu 2: Terminal menubar, notice the white rounded corner rectangles, it looks WAY uglier on other themes Note that the menubar isn't "ugly" in most contexts, but it still is on the desktops and some applications. (For the menubar, I think the terminal is the only one concerned by this) I tried going back to my original theme, it didn't fix the problem.

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  • robots.txt not updated

    - by Haridharan
    I have updated some url's and files in robots.txt file to block url's and files from google search results but, still files displaying in search results. As per a suggestion from a site I tried to update the robots.txt by below steps. In Google Webmaster tools, Health - Fetch as Google - type the url and click the fetch button. but, still files displaying in search results. Note: in Google Webmaster tools, Health - Blocked URL's - robots.txt file - downloaded date looks two dates back.

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  • Zotac MAG HD-ND01 Nettop review

    <b>Linux User and Developer:</b> "Like some of the alternative nettop computers we've reviewed over the past new months, the Zotac MAG can also attach to the VESA mount on the back of most monitors, meaning it takes up literally zero desk space."

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  • How come Indiegogo links shared on G+ link to their page instead of displaying URL?

    - by Ivan Vucica
    If an Indiegogo link, such as this one, gets shared on G+, their G+ page is displayed in the post in the place where commonly the URL would be displayed. I've tried looking analyzing the HTML, but came up empty handed: there's Twitter cards metadata, there's OpenGraph, there is a G+ button -- but I found nothing that links to Indiegogo's page, not even rel="publisher". So, how does Indiegogo achieve this?

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  • Sprite Animation Toolkits for iPhone

    - by Mike Eggleston
    Does anyone know of any good (and preferably free) Sprite Animation Toolkits/Libraries for iOS development? This library should be able to handle the collision detection and the movement of the sprites. Back in the 90's there was a Pascal library called Sprite Animation Toolkit by Ingemar Ragnemalm that handled a lot of the heft to create animations and the such. I am just wondering if there is anything like that in the iOS world?

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  • In esenthel engine how can I remove some object from Gui class?

    - by Gajet
    I know many people in this site may not know esenthel engine at all and my question may be better answered at engine forum but I'm putting it here to share the name of a real easy to code gameengine with all of you: you can easily add a Button for example to your GUI class (gui is it's shared instance) with Gui += buttonInstance.create("click on me") but I'm just wondering how can you remove an on object from from Gui members. as far as I know there is no such a method as removeChild or getChildren or anything similar.

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  • How to move from home page screen to the next menu screen on clicking a particular image in XNA4.0?

    - by Raj
    I m new 2 XNA game pgming(also C#)....I want 2 create a main page with some buttons and on clicking a particular button, it should goto another screen whr there r some buttons to select which should inturn goto the game screen on clicking....Whether I can put all the codes in the "game1.cs" or create new class for every page....Pls help... I've jus went through some pages in "Learning xna4.0" by o'reilly...If there s any other gud tutorials, pls suggest me...

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  • Visual Studio Extension: Web Essentials

    - by BizTalk Visionary
    To quote Scott Hanselman…. Visual Studio 2010 is really extensible and that's allowed many folks on the team to try out new features for Web Development without having to rebuild Visual Studio itself. One of those "playground" extensions is called "Web Essentials" by Mads Kristensen. Mads handles HTML5 and CSS3 tools for our team. You might remember Mads from when we released the Web Standards Update a few months back. Get it here: Scott Nanselman blog...

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  • Macbook Air freezes while running Ubuntu 13.10

    - by jjesse
    Ok folks I'm trying to setup my Macbook Air to run Ubuntu 13.10 (note: I normally using Kubuntu but currently running Ubuntu). I have run all of the updates for the system as of this posting. This happens regardless of the application I have open (Firefox, Terminal, Software Updater). The system will freeze, become unresponsive and then kick me back to the login screen. I don't see a crash notification or anything to send as troubleshooting so I don't know where to start

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  • How can I prioritize wireless networks with network-manager

    - by kynan
    Mostly I use my laptop in an environment where different wireless networks are available and I would like to preferably connect to one of those and only fall back to the other one if that one is not available. Is there any way of prioritizing which wireless networks network-manager preferably connects to? The only workaround I found so far was unchecking Connect Automatically in the options and re-enabling it when my preferred network is not available.

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  • What is happening to a domain with status PENDING DELETE as well as AUTORENEWPERIOD?

    - by Alex Angas
    A domain I once registered but gave away: Expiration Date:13-Mar-2013 14:39:45 UTC Sponsoring Registrar:Directi Internet Solutions Pvt. Ltd. dba PublicDomainRegistry.com (R159-LRMS) Status:PENDING DELETE RESTORABLE Status:HOLD Status:AUTORENEWPERIOD Status:REDEMPTIONPERIOD Registrant ID:DI_7838158 Registrant Name:scherhag Registrant Organization:Locafroid europe sa I'd like to get this domain back and I'm hoping that PENDING DELETE means it might soon be released to the market. However I'm not sure, as there is also a status that says AUTORENEWPERIOD?

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  • how search engines see reciprical links

    - by sam
    reciprical links cancel each other out from a search engines point of view but what counts as a recpirical link .. Do reciprical links work on a site level or an individual page level ? If you where to say get an in bound link from site-a.com to mysite.com and then linked back from blog.yoursite.com would that be reciprical. Im aware google sees subdomains as different domains all together but in this instance is that the same ?

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  • Book Review: Fast Track to MDX

    - by Greg Low
    Another book that I re-read while travelling last week was Fast Track to MDX . I still think that it's the best book that I've seen for introducing the core concepts of MDX. SolidQ colleague Mark Whitehorn, along with Mosha Pasumansky and Robert Zare do an amazing job of building MDX knowledge throughout the book. I had dinner with Mark in London a few years back and I was pestering him to update this book. The biggest limitation of the book is that it was written for SQL Server 2000 Analysis Services,...(read more)

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  • CodePlex Daily Summary for Friday, September 28, 2012

    CodePlex Daily Summary for Friday, September 28, 2012Popular ReleasesWPUtils: WPUtils 1.2: Just fixed an issue related to isolated storage path for ChoosePhotoBehavior. Specifically CreateDirectory method only accepts relative path, but was given a "/photos/" path which would result in exception. Please make sure you have this fix if you are using ChoosePhotoBehavior! NOTE: Windows Phone SDK 7.1 or higher is required.TFS Timesheets: TFS Timesheets 2.0: New features: Visual Studio 2012 support Bug fixes: Scaling mode inherited rather than font scalingCRM 2011 Visual Ribbon Editor: Visual Ribbon Editor 1.1 Beta: Visual Ribbon Editor 1.1 Beta What's New: Fixed scrolling issue in UnHide dialog Added support for connecting via ADFS / IFD Added support for more than one action for a button Added support for empty StringParameter for Javascript functions Fixed bug in rule CrmClientTypeRule when selecting Outlook option Extended Prefix field in New Button dialogFree Aspx Image Gallery: Free Aspx Image Gallery Release V1: This is first basic release of my free aspx image gallery project. It is free to use and modify by the user without any need of providing any credit to me.Simple Microsoft Excel Document Converter (Convert To XLS, XLSX, PDF, XPS): ExcelDocConverter 0.1 Beta: Initial Release Microsoft Excel Documents Converter. Microsoft Excel 1997-2003 (XLS) Microsoft Excel 2007/2010 (XLSX) Portable Document Format (PDF) Microsoft XPS Document (XPS) Difference between NET2.0 and NET3.5 This program uses .NET Framework runtime library to run. Basically, they are no differences. Only the runtime library version is different. For older computers, i.e. Windows XP, might not have .NET Framework 3.5 installed, then use NET2.0 in stead. But, some Windows XP SP2 mig...Office File Properties: Office File Properties 3.3.1: Bug fix. Convert file extension to lowercase before checking.LoBDb.NET: LoBDb.NET 1.0.9: Centido.Core library: 1) SQL Server script bug fix: an error when changing the MaxLength property of an indexed string column or when changing the Precision-Scale properties of a decimal column. LobDb.NET Manager: 1) Changing the Precision, Scale, Default Value, Minimum and Maximum properties of a decimal column now enables the Save button. 2) The MaxLength property of a string column and the Precision+Scale values of a decimal column are now displayed in the column list. 3) Changing the Min...Chaos games: Chaos games: Small app for generating fractals using chaos gamesVisual Studio Icon Patcher: Version 1.5.2: This version contains no new images from v1.5.1 Contains the following improvements: Better support for detecting the installed languages The extract & inject commands won’t run if Visual Studio is running You may now run in extract or inject mode The p/invoke code was cleaned up based on Code Analysis recommendations When a p/invoke method fails the Win32 error message is now displayed Error messages use red text Status messages use green textMCEBuddy 2.x: MCEBuddy 2.2.16: Changelog for 2.2.16 (32bit and 64bit) Now a standalone remote client also available to control the Engine remotely. 1. Added support for remote connections for status and configuration. MCEBuddy now uses port 23332. The remote server name, remote server port and local server port can be updated from the MCEBuddy.conf file BUT the Service or GUI needs to be restarted (i.e. reboot or restart service or restart program) for it to take effect. Refer to documentation for more details http://mce...ZXing.Net: ZXing.Net 0.9.0.0: On the way to a release 1.0 the API should be stable now with this version. sync with rev. 2393 of the java version improved api better Unity support Windows RT binaries Windows CE binaries new Windows Service demo new WPF demo WindowsCE Hotfix: Fixes an error with ISO8859-1 encoding and scannning of QR-Codes. The hotfix is only needed for the WindowsCE platform.SSIS GoogleAnalyticsSource: Version 1.1 Alpha 2: The component uses now the Google API V2.4 including the management API.MVC Bootstrap: MVC Boostrap 0.5.1: A small demo site, based on the default ASP.NET MVC 3 project template, showing off some of the features of MVC Bootstrap. This release uses Entity Framework 5 for data access and Ninject 3 for dependency injection. If you download and use this project, please give some feedback, good or bad!menu4web: menu4web 1.0 - free javascript menu for web sites: menu4web 1.0 has been tested with all major browsers: Firefox, Chrome, IE, Opera and Safari. Minified m4w.js library is less than 9K. Includes 21 menu examples of different styles. Can be freely distributed under The MIT License (MIT).Rawr: Rawr 5.0.0: This is the Downloadable WPF version of Rawr!For web-based version see http://elitistjerks.com/rawr.php You can find the version notes at: http://rawr.codeplex.com/wikipage?title=VersionNotes Rawr Addon (NOT UPDATED YET FOR MOP)We now have a Rawr Official Addon for in-game exporting and importing of character data hosted on Curse. The Addon does not perform calculations like Rawr, it simply shows your exported Rawr data in wow tooltips and lets you export your character to Rawr (including ba...Coevery - Free CRM: Coevery 1.0.0.26: The zh-CN issue has been solved. We also add a project management module.VidCoder: 1.4.1 Beta: Updated to HandBrake 4971. This should fix some issues with stuck PGS subtitles. Fixed build break which prevented pre-compiled XML serializers from showing up. Fixed problem where a preset would get errantly marked as modified when re-opening the encode settings window or importing a new preset.JSLint for Visual Studio 2010: 1.4.0: VS2012 support is alphaBlackJumboDog: Ver5.7.2: 2012.09.23 Ver5.7.2 (1)InetTest?? (2)HTTP?????????????????100???????????Player Framework by Microsoft: Player Framework for Windows 8 (Preview 6): IMPORTANT: List of breaking changes from preview 5 Added separate samples download with .vsix dependencies instead of source dependencies Support for FreeWheel SmartXML ad responses Support for Smooth Streaming SDK DownloaderPlugins Support for VMAP and TTML polling for live scenarios Support for custom smooth streaming byte stream and scheme handlers Support for new play time and position tracking plugin Added IsLiveChanged event Added AdaptivePlugin.MaxBitrate property Add...New ProjectsChaos games: Small app to generating fractals using chaos gamesDocument Digitalization System: This system will allow the users with on one or more PCs to digitalize pdf files and store it or export it to other file formats.ExternalTokenAnalysisOffline: SPUser?UserToken????????????????。FinalProjectSeniorProject: ***Unfinished*** Senior project build GL Ponpes Selamat Kendal: Aplikasi Akuntansi Sekolah Pondok Pesantren Modern Selamat KendalHealth Care Manager: One of keynote planned for the Brazzaville Microsoft event coming soon.Orchard Commerce History with PayPal: Project expands on Nwazet.Commerce module (and is required for this module to work). Adds a purchase history, product role associations, and PayPal.PDF.NET: PWMIS ?????? Ver 4.5 ???? SMS Egypt: This project is intended to make it easy for people to send SMS to their customers using SMS gateways inside and outside Egypt. Strong Caml: Use the familiar CAML syntax, but now do it in strongly-typed, dynamic code. Just follow Visual Studio's IntelliSense, and your CAML query can't go wrong!TrainingFrameWork: TrainingFrameWork

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  • Online ALTER TABLE in MySQL 5.6

    - by Marko Mäkelä
    This is the low-level view of data dictionary language (DDL) operations in the InnoDB storage engine in MySQL 5.6. John Russell gave a more high-level view in his blog post April 2012 Labs Release – Online DDL Improvements. MySQL before the InnoDB Plugin Traditionally, the MySQL storage engine interface has taken a minimalistic approach to data definition language. The only natively supported operations were CREATE TABLE, DROP TABLE and RENAME TABLE. Consider the following example: CREATE TABLE t(a INT); INSERT INTO t VALUES (1),(2),(3); CREATE INDEX a ON t(a); DROP TABLE t; The CREATE INDEX statement would be executed roughly as follows: CREATE TABLE temp(a INT, INDEX(a)); INSERT INTO temp SELECT * FROM t; RENAME TABLE t TO temp2; RENAME TABLE temp TO t; DROP TABLE temp2; You could imagine that the database could crash when copying all rows from the original table to the new one. For example, it could run out of file space. Then, on restart, InnoDB would roll back the huge INSERT transaction. To fix things a little, a hack was added to ha_innobase::write_row for committing the transaction every 10,000 rows. Still, it was frustrating that even a simple DROP INDEX would make the table unavailable for modifications for a long time. Fast Index Creation in the InnoDB Plugin of MySQL 5.1 MySQL 5.1 introduced a new interface for CREATE INDEX and DROP INDEX. The old table-copying approach can still be forced by SET old_alter_table=0. This interface is used in MySQL 5.5 and in the InnoDB Plugin for MySQL 5.1. Apart from the ability to do a quick DROP INDEX, the main advantage is that InnoDB will execute a merge-sort algorithm before inserting the index records into each index that is being created. This should speed up the insert into the secondary index B-trees and potentially result in a better B-tree fill factor. The 5.1 ALTER TABLE interface was not perfect. For example, DROP FOREIGN KEY still invoked the table copy. Renaming columns could conflict with InnoDB foreign key constraints. Combining ADD KEY and DROP KEY in ALTER TABLE was problematic and not atomic inside the storage engine. The ALTER TABLE interface in MySQL 5.6 The ALTER TABLE storage engine interface was completely rewritten in MySQL 5.6. Instead of introducing a method call for every conceivable operation, MySQL 5.6 introduced a handful of methods, and data structures that keep track of the requested changes. In MySQL 5.6, online ALTER TABLE operation can be requested by specifying LOCK=NONE. Also LOCK=SHARED and LOCK=EXCLUSIVE are available. The old-style table copying can be requested by ALGORITHM=COPY. That one will require at least LOCK=SHARED. From the InnoDB point of view, anything that is possible with LOCK=EXCLUSIVE is also possible with LOCK=SHARED. Most ALGORITHM=INPLACE operations inside InnoDB can be executed online (LOCK=NONE). InnoDB will always require an exclusive table lock in two phases of the operation. The execution phases are tied to a number of methods: handler::check_if_supported_inplace_alter Checks if the storage engine can perform all requested operations, and if so, what kind of locking is needed. handler::prepare_inplace_alter_table InnoDB uses this method to set up the data dictionary cache for upcoming CREATE INDEX operation. We need stubs for the new indexes, so that we can keep track of changes to the table during online index creation. Also, crash recovery would drop any indexes that were incomplete at the time of the crash. handler::inplace_alter_table In InnoDB, this method is used for creating secondary indexes or for rebuilding the table. This is the ‘main’ phase that can be executed online (with concurrent writes to the table). handler::commit_inplace_alter_table This is where the operation is committed or rolled back. Here, InnoDB would drop any indexes, rename any columns, drop or add foreign keys, and finalize a table rebuild or index creation. It would also discard any logs that were set up for online index creation or table rebuild. The prepare and commit phases require an exclusive lock, blocking all access to the table. If MySQL times out while upgrading the table meta-data lock for the commit phase, it will roll back the ALTER TABLE operation. In MySQL 5.6, data definition language operations are still not fully atomic, because the data dictionary is split. Part of it is inside InnoDB data dictionary tables. Part of the information is only available in the *.frm file, which is not covered by any crash recovery log. But, there is a single commit phase inside the storage engine. Online Secondary Index Creation It may occur that an index needs to be created on a new column to speed up queries. But, it may be unacceptable to block modifications on the table while creating the index. It turns out that it is conceptually not so hard to support online index creation. All we need is some more execution phases: Set up a stub for the index, for logging changes. Scan the table for index records. Sort the index records. Bulk load the index records. Apply the logged changes. Replace the stub with the actual index. Threads that modify the table will log the operations to the logs of each index that is being created. Errors, such as log overflow or uniqueness violations, will only be flagged by the ALTER TABLE thread. The log is conceptually similar to the InnoDB change buffer. The bulk load of index records will bypass record locking. We still generate redo log for writing the index pages. It would suffice to log page allocations only, and to flush the index pages from the buffer pool to the file system upon completion. Native ALTER TABLE Starting with MySQL 5.6, InnoDB supports most ALTER TABLE operations natively. The notable exceptions are changes to the column type, ADD FOREIGN KEY except when foreign_key_checks=0, and changes to tables that contain FULLTEXT indexes. The keyword ALGORITHM=INPLACE is somewhat misleading, because certain operations cannot be performed in-place. For example, changing the ROW_FORMAT of a table requires a rebuild. Online operation (LOCK=NONE) is not allowed in the following cases: when adding an AUTO_INCREMENT column, when the table contains FULLTEXT indexes or a hidden FTS_DOC_ID column, or when there are FOREIGN KEY constraints referring to the table, with ON…CASCADE or ON…SET NULL option. The FOREIGN KEY limitations are needed, because MySQL does not acquire meta-data locks on the child or parent tables when executing SQL statements. Theoretically, InnoDB could support operations like ADD COLUMN and DROP COLUMN in-place, by lazily converting the table to a newer format. This would require that the data dictionary keep multiple versions of the table definition. For simplicity, we will copy the entire table, even for DROP COLUMN. The bulk copying of the table will bypass record locking and undo logging. For facilitating online operation, a temporary log will be associated with the clustered index of table. Threads that modify the table will also write the changes to the log. When altering the table, we skip all records that have been marked for deletion. In this way, we can simply discard any undo log records that were not yet purged from the original table. Off-page columns, or BLOBs, are an important consideration. We suspend the purge of delete-marked records if it would free any off-page columns from the old table. This is because the BLOBs can be needed when applying changes from the log. We have special logging for handling the ROLLBACK of an INSERT that inserted new off-page columns. This is because the columns will be freed at rollback.

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    In Mac os x, I can move all windows to the nearest corner by hitting F11 key. I'm just wondering if there is a compiz plugin works like that. I know that there is Scale plugin already. But all that I want is something like this. You'll see, press a key and all windows fly off to nearest corner so I can drag/drop file or do something else on my desktop, then press the key again and all windows fly back.

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  • Search Engine Optimization - Article Branding Will Brand Your Business

    Branding your articles with your signature (a brief bio with each article) is the same as branding your business. This process helps to reach both goals in one shot. If you desire targeted traffic from the very start then give article marketing a serious shot and some serious effort. This form of marketing will also gain you multiple back links to your website of business and this is where your ranks start to increase.

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