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  • Accessing SQL Server data from iOS apps

    - by RobertChipperfield
    Almost all mobile apps need access to external data to be valuable. With a huge amount of existing business data residing in Microsoft SQL Server databases, and an ever-increasing drive to make more and more available to mobile users, how do you marry the rather separate worlds of Microsoft's SQL Server and Apple's iOS devices? The classic answer: write a web service layer Look at any of the questions on this topic asked in Internet discussion forums, and you'll inevitably see the answer, "just write a web service and use that!". But what does this process gain? For a well-designed database with a solid security model, and business logic in the database, writing a custom web service on top of this just to access some of the data from a different platform seems inefficient and unnecessary. Desktop applications interact with the SQL Server directly - why should mobile apps be any different? The better answer: the iSql SDK Working along the lines of "if you do something more than once, make it shared," we set about coming up with a better solution for the general case. And so the iSql SDK was born: sitting between SQL Server and your iOS apps, it provides the simple API you're used to if you've been developing desktop apps using the Microsoft SQL Native Client. It turns out a web service remained a sensible idea: HTTP is much more suited to the Big Bad Internet than SQL Server's native TDS protocol, removing the need for complex configuration, firewall configuration, and the like. However, rather than writing a web service for every app that needs data access, we made the web service generic, serving only as a proxy between the SQL Server and a client library integrated into the iPhone or iPad app. This client library handles all the network communication, and provides a clean API. OSQL in 25 lines of code As an example of how to use the API, I put together a very simple app that allowed the user to enter one or more SQL statements, and displayed the results in a rather primitively formatted text field. The total amount of Objective-C code responsible for doing the work? About 25 lines. You can see this in action in the demo video. Beta out now - your chance to give us your suggestions! We've released the iSql SDK as a beta on the MobileFoo website: you're welcome to download a copy, have a play in your own apps, and let us know what we've missed using the Feedback button on the site. Software development should be fun and rewarding: no-one wants to spend their time writing boiler-plate code over and over again, so stop writing the same web service code, and start doing exciting things in the new world of mobile data!

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  • Defensive Error Handling

    TRY…CATCH error handling in SQL Server has certain limitations and inconsistencies that will trap the unwary developer, used to the more feature-rich error handling of client-side languages such as C# and Java. In this article, abstracted from his excellent new book, Defensive Database Programming with SQL Server, Alex Kuznetsov offers a simple, robust approach to checking and handling errors in SQL Server, with client-side error handling used to enforce what is done on the server.

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  • On the art of self-promotion

    - by Tony Davis
    I attended Brent Ozar's Building the Fastest SQL Servers session at Tech Ed last week, and found myself engulfed in a 'perfect storm' of excellent technical and presentational skills coupled with an astute awareness of the value of promoting one's work. I spend a lot of time at such events talking to developers and DBAs about the value of blogging and writing articles, and my impression is that some could benefit from a touch less modesty and a little more self-promotion. I sense a reticence in many would-be writers. Is what I have to say important enough? Haven't far more qualified and established commentators, MVPs and so on, already said it? While it's a good idea to pick reasonably fresh and interesting topics, it's more important not to let such fears lead to writer's block. In the eyes of any future employer, your published writing is an extension of your resume. They will not care that a certain MVP knows how to solve problem x, but they will be very interested to see that you have tackled that same problem, and solved it in your own way, and described the process in your own voice. In your current job, your writing is one of the ways you can express to your peers, and to the organization as a whole, the value of what you contribute. Many Developers and DBAs seem to rely on the idea that their work will speak for itself, and that their skill shines out from it. Unfortunately, this isn't always true. Many Development DBAs, for example, will be painfully aware of the massive effort involved in tuning and adding resilience to rapidly developed applications. However, others in the organization who are unaware of what's involved in getting an application that is 'done' ready for production may dismiss such efforts as fussiness or conservatism. At the dark end of the development cycle, chickens come home to roost, but their droppings tend to land on those trying to clear up the mess. My advice is this: next time you fix a bug or improve the resilience or performance of a database or application, make sure that you use team meetings, informal discussions and so on to ensure that people understand what the problem was and what you had to do to fix it. Use your blog to describe, generally, the process you adopted, the resources you used and the insights that came from your work. Encourage your colleagues to do the same. By spreading the art of self-promotion to everyone involved in an IT project, we get a better idea of the extent of the work and the value of the contribution of all the team members. As always, we'd love to hear what you think. This very week, Simple-talk launches its new blogging platform. If any of this has moved you to 'throw your hat into the ring', drop us a mail at [email protected]. Cheers, Tony.

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  • Obfuscating Silverlight with SmartAssembly

    If you are in the .NET Software business, you have a problem. .NET assemblies can be read, and debugged, by the purchaser with almost the same ease as if you'd distributed the source code. This isn't always what you wanted or intended, so you'll need an application such as Smart Assembly. Khawar explains the simple process of protecting your company's assets.

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  • Yet Another SQL Strategy for Versioned Data

    There is a popular design for a database that requires a built-in audit-trail of amendments and additions, where data is never deleted, but merely superseded by a later version. Whilst this is conceptually simple, it has always made for complicated SQL for reporting the latest version of data. Alex joins the debate on the best way of doing this with an example using an indexed view and the filtered index.

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  • SQL Server Unit Testing with tSQLt

    When one considers the amount of time and effort that Unit Testing consumes for the Database Developer, is surprising how few good SQL Server Test frameworks are around. tSQLt , which is open source and free to use, is one of the frameworks that provide a simple way to populate a table with test data as part of the unit test, and check the results with what should be expected. Sebastian and Dennis, who created tSQLt, explain.

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  • A TDD Journey: 4-Tests as Documentation; False Positive Results; Component Isolation

    In Test-Driven Development (TDD) , The writing of a unit test is done more to design and to document than to verifiy. By writing a unit test you close a number of feedback loops, and verifying the functionality of the code is just a minor one. everything you need to know about your class under test is embodied in a simple list of the names of the tests. Michael Sorens continues his introduction to TDD that is more of a journey in six parts, by discussing Tests as Documentation, False Positive Results and Component Isolation.

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  • Where to store short strings (with my key) on the internet?

    - by Vi
    Is there simple service to store strings under my key that can be used by bots? Requirements: Simple command line access, automatic posting allowed No need to keep some session with the service alive I choose the key (so pastebins fail) No requirement for registration/authentication (for simplicity) The string should be kept for about a month. I want something like: Store: $ echo some_data_0x1299C0FF | store_my_string testtest2011 Retrieve: $ retrive_my_string testtest2011 some_data_0x1299C0FF Do you have ideas what should I use for it? I can only think of using IRC somehow (channel topics, /whowas, ...), but this is too complex for this simple task. No security is needed: anyone can update my string. The task looks very simple, so I expect the solution to be similarly simple. Expecting something like single simple curl call.

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  • Permanent fix for unicode characters not displaying correctly (as boxes)

    - by Chase
    Please read this entire message before replying. First I know how to fix the issue on a temporary basis. I am looking for a permanent fix. I work with foreign language files a lot. Unfortunately sometimes all the unicode characters in windows explorer, notepad, and other places (as rendered by windows, probably GDI) do not display correctly. That is they display as square blocks, where as they had just been displaying correctly. There are countless methods to temporarily correct the issue. But again, I want a way to permanently resolve the issue. What I have tried: The silly "Hide fonts based on language settings". This setting only applies to what fonts you see in the fonts folder and font dropdowns. It doesn't disable foreign fonts (doesn't work, or if it does, it is temporary). Deleting the font cache file and rebooting (works.. usually, temporary solution). Changing my locale and then back (sometimes works, temporary solution). Rebooting my PC and getting lucky (50-50 chance, temporary solution). Changing my keyboard input/adding foreign keyboard (temporary solution that only seems to work once). Reinstalling windows (temporary solution, sometimes lasts a few months though, I have done this 7 times across 3 computers) What I have not tried: Buying Windows Ultimate and installing the interface packs. This is not a solution. I can't read Japanese/Chinese and I do not want my interface in those languages. What I will not do: Switch to a different brand operating system (unix, linux, mac os x) Switch to an older version of windows (Windows Vista, XP, 2000, etc). So can anyone recommend a permanent fix for the problem?

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  • Exitus Acta Probat: The Post-Processing Module

    - by Phil Factor
    Sometimes, one has to make certain ethical compromises to ensure the success of a corporate IT project. Exitus Acta Probat (literally 'the result validates the deeds' meaning that the ends justify the means)It was a while back, whilst working as a Technical Architect for a well-known international company, that I was given the task of designing the architecture of a rather specialized accounting system. We'd tried an off-the-shelf (OTS) Windows-based solution which crashed with dispiriting regularity, and didn't quite do what the business required. After a great deal of research and planning, we commissioned a Unux-based system that used X-terminals for the desktops of  the participating staff. X terminals are now obsolete, but were then hot stuff; stripped-down Unix workstations that provided client GUIs for networked applications long before the days of AJAX, Flash, Air and DHTML. I've never known a project go so smoothly: I'd been initially rather nervous about going the Unix route, believing then that  Unix programmers were excitable creatures who were prone to  indulge in role-play enactments of elves and wizards at the weekend, but the programmers I met from the company that did the work seemed to be rather donnish, earnest, people who quickly grasped our requirements and were faultlessly professional in their work.After thinking lofty thoughts for a while, there was considerable pummeling of keyboards by our suppliers, and a beautiful robust application was delivered to us ahead of dates.Soon, the department who had commissioned the work received shiny new X Terminals to replace their rather depressing lavatory-beige PCs. I modestly hung around as the application was commissioned and deployed to the department in order to receive the plaudits. They didn't come. Something was very wrong with the project. I couldn't put my finger on the problem, and the users weren't doing any more than desperately and futilely searching the application to find a fault with it.Many times in my life, I've come up against a predicament like this: The roll-out of an application goes wrong and you are hearing nothing that helps you to discern the cause but nit-*** noise. There is a limit to the emotional heat you can pack into a complaint about text being in the wrong font, or an input form being slightly cramped, but they tried their best. The answer is, of course, one that every IT executive should have tattooed prominently where they can read it in emergencies: In Vino Veritas (literally, 'in wine the truth', alcohol loosens the tongue. A roman proverb) It was time to slap the wallet and get the department down the pub with the tab in my name. It was an eye-watering investment, but hedged with an over-confident IT director who relished my discomfort. To cut a long story short, The real reason gushed out with the third round. We had deprived them of their PCs, which had been good for very little from the pure business perspective, but had provided them with many hours of happiness playing computer-based minesweeper and solitaire. There is no more agreeable way of passing away the interminable hours of wage-slavery than minesweeper or solitaire, and the employees had applauded the munificence of their employer who had provided them with the means to play it. I had, unthinkingly, deprived them of it.I held an emergency meeting with our suppliers the following day. I came over big with the notion that it was in their interests to provide a solution. They played it cool, probably knowing that it was my head on the block, not theirs. In the end, they came up with a compromise. they would temporarily descend from their lofty, cerebral stamping grounds  in order to write a server-based Minesweeper and Solitaire game for X Terminals, and install it in a concealed place within the system. We'd have to pay for it, though. I groaned. How could we do that? "Could we call it a 'post-processing module?" suggested their account executive.And so it came to pass. The application was a resounding success. Every now and then, the staff were able to indulge in some 'post-processing', with what turned out to be a very fine implementation of both minesweeper and solitaire. There were several refinements: A single click in a 'boss' button turned the games into what looked just like a financial spreadsheet.  They even threw in a multi-user version of Battleships. The extra payment for the post-processing module went through the change-control process without anyone untoward noticing, and peace once more descended. Only one thing niggles. Those games were good. Do they still survive, somewhere in a Linux library? If so, I'd like to claim a small part in their production.

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  • Database Owner Conundrum

    - by Johnm
    Have you ever restored a database from a production environment on Server A into a development environment on Server B and had some items, such as Service Broker, mysteriously cease functioning? You might want to consider reviewing the database owner property of the database. The Scenario Recently, I was developing some messaging functionality that utilized the Service Broker feature of SQL Server in a development environment. Within the instance of the development environment resided two databases: One was a restored version of a production database that we will call "RestoreDB". The second database was a brand new database that has yet to exist in the production environment that we will call "DevDB". The goal is to setup a communication path between RestoreDB and DevDB that will later be implemented into the production database. After implementing all of the Service Broker objects that are required to communicate within a database as well as between two databases on the same instance I found myself a bit confounded. My testing was showing that the communication was successful when it was occurring internally within DevDB; but the communication between RestoreDB and DevDB did not appear to be working. Profiler to the rescue After carefully reviewing my code for any misspellings, missing commas or any other minor items that might be a syntactical cause of failure, I decided to launch Profiler to aid in the troubleshooting. After simulating the cross database messaging, I noticed the following error appearing in Profiler: An exception occurred while enqueueing a message in the target queue. Error: 33009, State: 2. The database owner SID recorded in the master database differs from the database owner SID recorded in database '[Database Name Here]'. You should correct this situation by resetting the owner of database '[Database Name Here]' using the ALTER AUTHORIZATION statement. Now, this error message is a helpful one. Not only does it identify the issue in plain language, it also provides a potential solution. An execution of the following query that utilizes the catalog view sys.transmission_queue revealed the same error message for each communication attempt: SELECT     * FROM        sys.transmission_queue; Seeing the situation as a learning opportunity I dove a bit deeper. Reviewing the database properties  The owner of a specific database can be easily viewed by right-clicking the database in SQL Server Management Studio and selecting the "properties" option. The owner is listed on the "General" page of the properties screen. In my scenario, the database in the production server was created by Frank the DBA; therefore his server login appeared as the owner: "ServerName\Frank". While this is interesting information, it certainly doesn't tell me much in regard to the SID (security identifier) and its existence, or lack thereof, in the master database as the error suggested. I pulled together the following query to gather more interesting information: SELECT     a.name     , a.owner_sid     , b.sid     , b.name     , b.type_desc FROM        master.sys.databases a     LEFT OUTER JOIN master.sys.server_principals b         ON a.owner_sid = b.sid WHERE     a.name not in ('master','tempdb','model','msdb'); This query also helped identify how many other user databases in the instance were experiencing the same issue. In this scenario, I saw that there were no matching SIDs in server_principals to the owner SID for my database. What login should be used as the database owner instead of Frank's? The system stored procedure sp_helplogins will provide a list of the valid logins that can be used. Here is an example of its use, revealing all available logins: EXEC sp_helplogins;  Fixing a hole The error message stated that the recommended solution was to execute the ALTER AUTHORIZATION statement. The full statement for this scenario would appear as follows: ALTER AUTHORIZATION ON DATABASE:: [Database Name Here] TO [Login Name]; Another option is to execute the following statement using the sp_changedbowner system stored procedure; but please keep in mind that this stored procedure has been deprecated and will likely disappear in future versions of SQL Server: EXEC dbo.sp_changedbowner @loginname = [Login Name]; .And They Lived Happily Ever After Upon changing the database owner to an existing login and simulating the inner and cross database messaging the errors have ceased. More importantly, all messages sent through this feature now successfully complete their journey. I have added the ownership change to my restoration script for the development environment.

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  • DIVs of equal height

    - by Richard Mitchell
    It's the same old old problem you want to make a set of columns the same height but life it too short for the CSS only version. It's technically possible to do but nowadays you can't run the web without having javascript turned on. There must be an easier way. After a short amount of googling I came across a few solutions. A couple were GPL'd which ruled them straight out as I want Red Gate to pay for my mortgage. The best simple solution was found at. http://www.cssnewbie.com/equal-height-columns-with-jquery/...(read more)

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  • IE HTML Debugger Causing Issues with IE Enhanced Security

    - by Damon
    In an effort to debug a Silverlight component on a page in SharePoint I opened the Developer Tools in Internet Explorer.  After choosing the Find > Select Element by Click option my page refreshed for some reason and a small bar appeared at the top of the page reading: You may be trying to access this site from a secured browser on the server. Please enable scripts and reload this page. After a quick look around the internet, some seemed to be suggesting that you have to disable the Internet Explorer Enhanced Security Configuration (IE ESC) in Server Manager.  Since this is one of the very first things I do when creating a VM, I figured the solution did not apply to me.  However, I decided to go ahead and enable IE ESC and then disable it again to see if that would fix the problem, and it did.  So if you see that error message in IE, the bar and you've already got IE ESC disabled, you can just enable it and disable it to get rid of the bar.

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  • How to Enable SideLoading in a SharePoint Site

    - by Damon Armstrong
    I was trying to deploy a SharePoint App for the first time and ran into an error about SideLoading not being enabled on the site. The solution is fairly simple – you just have enable the Developer feature on the site.  Unfortunately, it’s a hidden feature so you have to do it through PowerShell.  While searching the internet for the command to enable the feature I kept running into really long scripts that seemed overly complicated.  Fortunately, Jeff (a friend at work) sent me this snippet that is very concise and does the job: Enable-SPFeature e374875e-06b6-11e0-b0fa-57f5dfd72085 –url http://yoursharepointbox/site/ Obviously, you will need to update the URL to match your environment!

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  • How to encrypt dual boot windows 7 and xp (bitlocker, truecrypt combo?) on sdd (recommended?)

    - by therobyouknow
    I would like to setup a dual boot Windows 7 and Windows XP laptop/notebook computer where each operation system's partition is fully encrypted. I would like to do this on a SSD - a 128Gb Crucial M4. My research Dual boot of truecrypt encrypted OSs on one drive (not possible - in Truecript 7.x at time of writing) This cannot be done on a standard Truecrypt setup - it will only support encrypting one of the operating systems. I have tried this and also read about it here on superuser.com However, I did see a solution here that uses grub4dos as the initial bootloader to chain to separate truecrypt encrypted OSs, in my case Windows 7 and Windows XP: http://yyzyyz.blogspot.co.uk/2010/06/truecrypt-how-to-encrypt-multiple.html I am not going to consider this solution as it relies upon some custom code for use in the bootloader that is provided by the author. I would prefer a solution that can be fully understood so that I can be sure that there is nothing undesirable occuring (i.e. malware or just simply bugs in the code). I would like to believe such a solution doesn't have those risks but I can't be sure. BitLocker and Truecrypt combination - possible solution? So I am now considering a combination of encryption programs: I now aim to encrypt Windows XP with Truecrypt and Windows 7 with BitLocker. Assuming Truecrypt bootloader can boot into non-Truecrypt OSs (e.g. via hitting Escape to go to another menu), then this solution may be viable. SSDs and Encryption (use fastest possible spinning hard disk instead (?)) I read on various superuser.com posts and elsewhere that current SSDs are not suited to whole drive encryption for various reasons: impact of performance algorithms that give SSDs advantage over spinning harddisks. Algorithms used in compression of data for example. Wear on the SSD, shortening its life Security issues whereby data is repeated, as indicated in some Truecrypt documentation So I am now considering not using SSD. But with the aim to have the fastest drive possible, I am considering using the Western Digital Scorpion black 2.5" 7200rpm harddisk as this appears to be top rated among spinning platter-based harddrives (don't work for Western Digital). Summary So to achieve whole drive encrypted dual boot Windows 7 and Windows XP with minimal performance impact I intend to use a combination of Truecrypt and Bitlocker on a top-rated conventional spinning platter-based harddisk. Questions Will my summary: achieve whole disk encryption of the dual-boot Windows XP, Windows 7? OR an you suggest a simpler solution, including one that only requires only Truecrypt (BitLocker not available on XP). Or another encryption tool, including paid-for? provide the highest performance. Am I correct to avoid using SDD with encryption for the reasons I discovered? Are the concerns about SSDs and encryption still very real (some articles I read go back to 2010) Thanks for your input!

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  • Problem Installing older TestNG plugin on Eclipse 3.5

    - by Stefan
    I'm trying to install TestNG 5.11 on eclipse 3.5 and gettign the following. eclipse.buildId=unknown java.version=1.6.0_19 java.vendor=Sun Microsystems Inc. BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=no_NO Framework arguments: -product org.eclipse.epp.package.jee.product Command-line arguments: -os win32 -ws win32 -arch x86 -product org.eclipse.epp.package.jee.product Error Mon Jun 07 15:45:53 CEST 2010 Artifact not found: org.eclipse.update.feature,org.testng.eclipse,5.11.0.28. java.io.FileNotFoundException: "http://beust.com/eclipse/features/org.testng.eclipse_5.11.0.28.jar" at org.eclipse.equinox.internal.p2.repository.RepositoryStatusHelper.checkFileNotFound(RepositoryStatusHelper.java:289) at org.eclipse.equinox.internal.p2.repository.FileReader.checkException(FileReader.java:352) at org.eclipse.equinox.internal.p2.repository.FileReader.sendRetrieveRequest(FileReader.java:326) at org.eclipse.equinox.internal.p2.repository.FileReader.readInto(FileReader.java:263) at org.eclipse.equinox.internal.p2.repository.RepositoryTransport.download(RepositoryTransport.java:71) at org.eclipse.equinox.internal.p2.repository.RepositoryTransport.download(RepositoryTransport.java:127) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.downloadArtifact(SimpleArtifactRepository.java:468) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.downloadArtifact(SimpleArtifactRepository.java:451) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.getArtifact(SimpleArtifactRepository.java:518) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.getArtifact(MirrorRequest.java:200) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.transferSingle(MirrorRequest.java:175) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.transfer(MirrorRequest.java:159) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.perform(MirrorRequest.java:95) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.getArtifact(SimpleArtifactRepository.java:507) at org.eclipse.equinox.internal.p2.artifact.repository.simple.DownloadJob.run(DownloadJob.java:64) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55) Error Mon Jun 07 15:45:53 CEST 2010 Artifact not found: osgi.bundle,org.testng.eclipse,5.11.0.28. java.io.FileNotFoundException: "http://beust.com/eclipse/plugins/org.testng.eclipse_5.11.0.28.jar" at org.eclipse.equinox.internal.p2.repository.RepositoryStatusHelper.checkFileNotFound(RepositoryStatusHelper.java:289) at org.eclipse.equinox.internal.p2.repository.FileReader.checkException(FileReader.java:352) at org.eclipse.equinox.internal.p2.repository.FileReader.sendRetrieveRequest(FileReader.java:326) at org.eclipse.equinox.internal.p2.repository.FileReader.readInto(FileReader.java:263) at org.eclipse.equinox.internal.p2.repository.RepositoryTransport.download(RepositoryTransport.java:71) at org.eclipse.equinox.internal.p2.repository.RepositoryTransport.download(RepositoryTransport.java:127) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.downloadArtifact(SimpleArtifactRepository.java:468) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.downloadArtifact(SimpleArtifactRepository.java:451) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.getArtifact(SimpleArtifactRepository.java:518) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.getArtifact(MirrorRequest.java:200) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.transferSingle(MirrorRequest.java:175) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.transfer(MirrorRequest.java:159) at org.eclipse.equinox.internal.p2.artifact.repository.MirrorRequest.perform(MirrorRequest.java:95) at org.eclipse.equinox.internal.p2.artifact.repository.simple.SimpleArtifactRepository.getArtifact(SimpleArtifactRepository.java:507) at org.eclipse.equinox.internal.p2.artifact.repository.simple.DownloadJob.run(DownloadJob.java:64) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55) Error Mon Jun 07 15:45:53 CEST 2010 session context was:(profile=epp.package.jee, phase=org.eclipse.equinox.internal.provisional.p2.engine.phases.Collect, operand=, action=). I'm kinda stuck so I would really like help. Thanks

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  • server health monitor

    - by arash
    hello i need to a server monitoring solution. the solution must be able to alert when a server goes down also i want, the solution be flexible to work with various servers for example it must be able to monitor servers like, webserver,application server, DB server and ... i want to know is any open source solution is available for me? thanks in advance

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  • Can't access font resource in Silverlight class library

    - by Matt
    I have a reasonably large Silveright 3.0 project on the go, and I'm having issues accessing a couple of custom font resources from within one of the assemblies. I've got a working test solution where I have added a custom font as a resource, and can access it fine from XAML using: <TextBlock Text="Test" FontFamily="FontName.ttf#Font Name" /> The test solution consists of the TestProject.Application and the TestProject.Application.Web projects, with all the fun and games obviously in the TestProject.Application project However, when I try this in my main solution, the fonts refuse to show in the correct type face (instead showing in the default font). There's no difference in the way the font has been added to project between the test solution and the main solution, and the XAML is identical. However, there is a solution layout difference. In the main solution, as well as having a MainApp.Application and MainApp.Application.Web project, I also have a MainApp.Application.ViewModel project and a MainApp.Application.Views project, and the problem piece of XAML is the in the MainApp.Application.Views project (not the .Application project like the test solution). I've tried putting the font into either the .Application or .Application.Views project, tried changing the Build Action to Content, Embedded Resource etc, all to no avail. So, is there an issue accessing font resources from a child assembly that I don't know about, or has anyone successfully done this? My long term need will be to have the valid custom fonts being stored as resources in a separate .Application.FontLibrary assembly that will be on-demand downloaded and cached, and the XAML controls in the .Application.Views project will need to reference this FontLibrary assembly to get the valid fonts. I've also tried xcreating this separate font library assembly, and I can't seem to get the fonts from the second assembly. As some additional information, I've also tried the following font referencing approaches: <TextBlock Text="Test" FontFamily="/FontName.ttf#Font Name" /> <TextBlock Text="Test" FontFamily="pack:application,,,/FontName.ttf#Font Name" /> <TextBlock Text="Test" FontFamily="pack:application,,,/MainApp.Application.Views;/FontName.ttf#Font Name" /> <TextBlock Text="Test" FontFamily="pack:application,,,/MainApp.Application.Views;component/FontName.ttf#Font Name" /> And a few similar variants with different assembly references/sub directories/random semi colons. And so far nothing works... anyone struck this (and preferably solved it)?

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  • How do I move my git repo down level in the directory tree?

    - by edude05
    I'm currently writing an app in C# using using Visual Studio. As such, VS2010 created a Solution directory with my project directories inside. So my Hierarchy is like this: Solution .git project1 project2 What I'd like to do is make it like this: Solution Project 1 .git Project 2 As of right now the files in the solution are tracked, except for the project 2 (so stuff like project.sln for example). Is there a way I can do this without rewriting the history? Thanks in advance.

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  • Getting a Database into Source Control

    - by Grant Fritchey
    For any number of reasons, from simple auditing, to change tracking, to automated deployment, to integration with application development processes, you’re going to want to place your database into source control. Using Red Gate SQL Source Control this process is extremely simple. SQL Source Control works within your SQL Server Management Studio (SSMS) interface.  This means you can work with your databases in any way that you’re used to working with them. If you prefer scripts to using the GUI, not a problem. If you prefer using the GUI to having to learn T-SQL, again, that’s fine. After installing SQL Source Control, this is what you’ll see when you open SSMS:   SQL Source Control is now a direct piece of the SSMS environment. The key point initially is that I currently don’t have a database selected. You can even see that in the SQL Source Control window where it shows, in red, “No database selected – select a database in Object Explorer.” If I expand my Databases list in the Object Explorer, you’ll be able to immediately see which databases have been integrated with source control and which have not. There are visible differences between the databases as you can see here:   To add a database to source control, I first have to select it. For this example, I’m going to add the AdventureWorks2012 database to an instance of the SVN source control software (I’m using uberSVN). When I click on the AdventureWorks2012 database, the SQL Source Control screen changes:   I’m going to need to click on the “Link database to source control” text which will open up a window for connecting this database to the source control system of my choice.  You can pick from the default source control systems on the left, or define one of your own. I also have to provide the connection string for the location within the source control system where I’ll be storing my database code. I set these up in advance. You’ll need two. One for the main set of scripts and one for special scripts called Migrations that deal with different kinds of changes between versions of the code. Migrations help you solve problems like having to create or modify data in columns as part of a structural change. I’ll talk more about them another day. Finally, I have to determine if this is an isolated environment that I’m going to be the only one use, a dedicated database. Or, if I’m sharing the database in a shared environment with other developers, a shared database.  The main difference is, under a dedicated database, I will need to regularly get any changes that other developers have made from source control and integrate it into my database. While, under a shared database, all changes for all developers are made at the same time, which means you could commit other peoples work without proper testing. It all depends on the type of environment you work within. But, when it’s all set, it will look like this: SQL Source Control will compare the results between the empty folders in source control and the database, AdventureWorks2012. You’ll get a report showing exactly the list of differences and you can choose which ones will get checked into source control. Each of the database objects is scripted individually. You’ll be able to modify them later in the same way. Here’s the list of differences for my new database:   You can select/deselect all the objects or each object individually. You also get a report showing the differences between what’s in the database and what’s in source control. If there was already a database in source control, you’d only see changes to database objects rather than every single object. You can see that the database objects can be sorted by name, by type, or other choices. I’m going to add a comment such as “Initial creation of database in source control.” And then click on the Commit button which will put all the objects in my database into the source control system. That’s all it takes to get the objects into source control initially. Now is when things can get fun with breaking changes to code, automated deployments, unit testing and all the rest.

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  • Microsoft Introduces WebMatrix

    - by Rick Strahl
    originally published in CoDe Magazine Editorial Microsoft recently released the first CTP of a new development environment called WebMatrix, which along with some of its supporting technologies are squarely aimed at making the Microsoft Web Platform more approachable for first-time developers and hobbyists. But in the process, it also provides some updated technologies that can make life easier for existing .NET developers. Let’s face it: ASP.NET development isn’t exactly trivial unless you already have a fair bit of familiarity with sophisticated development practices. Stick a non-developer in front of Visual Studio .NET or even the Visual Web Developer Express edition and it’s not likely that the person in front of the screen will be very productive or feel inspired. Yet other technologies like PHP and even classic ASP did provide the ability for non-developers and hobbyists to become reasonably proficient in creating basic web content quickly and efficiently. WebMatrix appears to be Microsoft’s attempt to bring back some of that simplicity with a number of technologies and tools. The key is to provide a friendly and fully self-contained development environment that provides all the tools needed to build an application in one place, as well as tools that allow publishing of content and databases easily to the web server. WebMatrix is made up of several components and technologies: IIS Developer Express IIS Developer Express is a new, self-contained development web server that is fully compatible with IIS 7.5 and based on the same codebase that IIS 7.5 uses. This new development server replaces the much less compatible Cassini web server that’s been used in Visual Studio and the Express editions. IIS Express addresses a few shortcomings of the Cassini server such as the inability to serve custom ISAPI extensions (i.e., things like PHP or ASP classic for example), as well as not supporting advanced authentication. IIS Developer Express provides most of the IIS 7.5 feature set providing much better compatibility between development and live deployment scenarios. SQL Server Compact 4.0 Database access is a key component for most web-driven applications, but on the Microsoft stack this has mostly meant you have to use SQL Server or SQL Server Express. SQL Server Compact is not new-it’s been around for a few years, but it’s been severely hobbled in the past by terrible tool support and the inability to support more than a single connection in Microsoft’s attempt to avoid losing SQL Server licensing. The new release of SQL Server Compact 4.0 supports multiple connections and you can run it in ASP.NET web applications simply by installing an assembly into the bin folder of the web application. In effect, you don’t have to install a special system configuration to run SQL Compact as it is a drop-in database engine: Copy the small assembly into your BIN folder (or from the GAC if installed fully), create a connection string against a local file-based database file, and then start firing SQL requests. Additionally WebMatrix includes nice tools to edit the database tables and files, along with tools to easily upsize (and hopefully downsize in the future) to full SQL Server. This is a big win, pending compatibility and performance limits. In my simple testing the data engine performed well enough for small data sets. This is not only useful for web applications, but also for desktop applications for which a fully installed SQL engine like SQL Server would be overkill. Having a local data store in those applications that can potentially be accessed by multiple users is a welcome feature. ASP.NET Razor View Engine What? Yet another native ASP.NET view engine? We already have Web Forms and various different flavors of using that view engine with Web Forms and MVC. Do we really need another? Microsoft thinks so, and Razor is an implementation of a lightweight, script-only view engine. Unlike the Web Forms view engine, Razor works only with inline code, snippets, and markup; therefore, it is more in line with current thinking of what a view engine should represent. There’s no support for a “page model” or any of the other Web Forms features of the full-page framework, but just a lightweight scripting engine that works with plain markup plus embedded expressions and code. The markup syntax for Razor is geared for minimal typing, plus some progressive detection of where a script block/expression starts and ends. This results in a much leaner syntax than the typical ASP.NET Web Forms alligator (<% %>) tags. Razor uses the @ sign plus standard C# (or Visual Basic) block syntax to delineate code snippets and expressions. Here’s a very simple example of what Razor markup looks like along with some comment annotations: <!DOCTYPE html> <html>     <head>         <title></title>     </head>     <body>     <h1>Razor Test</h1>          <!-- simple expressions -->     @DateTime.Now     <hr />     <!-- method expressions -->     @DateTime.Now.ToString("T")          <!-- code blocks -->     @{         List<string> names = new List<string>();         names.Add("Rick");         names.Add("Markus");         names.Add("Claudio");         names.Add("Kevin");     }          <!-- structured block statements -->     <ul>     @foreach(string name in names){             <li>@name</li>     }     </ul>           <!-- Conditional code -->        @if(true) {                        <!-- Literal Text embedding in code -->        <text>         true        </text>;    }    else    {        <!-- Literal Text embedding in code -->       <text>       false       </text>;    }    </body> </html> Like the Web Forms view engine, Razor parses pages into code, and then executes that run-time compiled code. Effectively a “page” becomes a code file with markup becoming literal text written into the Response stream, code snippets becoming raw code, and expressions being written out with Response.Write(). The code generated from Razor doesn’t look much different from similar Web Forms code that only uses script tags; so although the syntax may look different, the operational model is fairly similar to the Web Forms engine minus the overhead of the large Page object model. However, there are differences: -Razor pages are based on a new base class, Microsoft.WebPages.WebPage, which is hosted in the Microsoft.WebPages assembly that houses all the Razor engine parsing and processing logic. Browsing through the assembly (in the generated ASP.NET Temporary Files folder or GAC) will give you a good idea of the functionality that Razor provides. If you look closely, a lot of the feature set matches ASP.NET MVC’s view implementation as well as many of the helper classes found in MVC. It’s not hard to guess the motivation for this sort of view engine: For beginning developers the simple markup syntax is easier to work with, although you obviously still need to have some understanding of the .NET Framework in order to create dynamic content. The syntax is easier to read and grok and much shorter to type than ASP.NET alligator tags (<% %>) and also easier to understand aesthetically what’s happening in the markup code. Razor also is a better fit for Microsoft’s vision of ASP.NET MVC: It’s a new view engine without the baggage of Web Forms attached to it. The engine is more lightweight since it doesn’t carry all the features and object model of Web Forms with it and it can be instantiated directly outside of the HTTP environment, which has been rather tricky to do for the Web Forms view engine. Having a standalone script parser is a huge win for other applications as well – it makes it much easier to create script or meta driven output generators for many types of applications from code/screen generators, to simple form letters to data merging applications with user customizability. For me personally this is very useful side effect and who knows maybe Microsoft will actually standardize they’re scripting engines (die T4 die!) on this engine. Razor also better fits the “view-based” approach where the view is supposed to be mostly a visual representation that doesn’t hold much, if any, code. While you can still use code, the code you do write has to be self-contained. Overall I wouldn’t be surprised if Razor will become the new standard view engine for MVC in the future – and in fact there have been announcements recently that Razor will become the default script engine in ASP.NET MVC 3.0. Razor can also be used in existing Web Forms and MVC applications, although that’s not working currently unless you manually configure the script mappings and add the appropriate assemblies. It’s possible to do it, but it’s probably better to wait until Microsoft releases official support for Razor scripts in Visual Studio. Once that happens, you can simply drop .cshtml and .vbhtml pages into an existing ASP.NET project and they will work side by side with classic ASP.NET pages. WebMatrix Development Environment To tie all of these three technologies together, Microsoft is shipping WebMatrix with an integrated development environment. An integrated gallery manager makes it easy to download and load existing projects, and then extend them with custom functionality. It seems to be a prominent goal to provide community-oriented content that can act as a starting point, be it via a custom templates or a complete standard application. The IDE includes a project manager that works with a single project and provides an integrated IDE/editor for editing the .cshtml and .vbhtml pages. A run button allows you to quickly run pages in the project manager in a variety of browsers. There’s no debugging support for code at this time. Note that Razor pages don’t require explicit compilation, so making a change, saving, and then refreshing your page in the browser is all that’s needed to see changes while testing an application locally. It’s essentially using the auto-compiling Web Project that was introduced with .NET 2.0. All code is compiled during run time into dynamically created assemblies in the ASP.NET temp folder. WebMatrix also has PHP Editing support with syntax highlighting. You can load various PHP-based applications from the WebMatrix Web Gallery directly into the IDE. Most of the Web Gallery applications are ready to install and run without further configuration, with Wizards taking you through installation of tools, dependencies, and configuration of the database as needed. WebMatrix leverages the Web Platform installer to pull the pieces down from websites in a tight integration of tools that worked nicely for the four or five applications I tried this out on. Click a couple of check boxes and fill in a few simple configuration options and you end up with a running application that’s ready to be customized. Nice! You can easily deploy completed applications via WebDeploy (to an IIS server) or FTP directly from within the development environment. The deploy tool also can handle automatically uploading and installing the database and all related assemblies required, making deployment a simple one-click install step. Simplified Database Access The IDE contains a database editor that can edit SQL Compact and SQL Server databases. There is also a Database helper class that facilitates database access by providing easy-to-use, high-level query execution and iteration methods: @{       var db = Database.OpenFile("FirstApp.sdf");     string sql = "select * from customers where Id > @0"; } <ul> @foreach(var row in db.Query(sql,1)){         <li>@row.FirstName @row.LastName</li> } </ul> The query function takes a SQL statement plus any number of positional (@0,@1 etc.) SQL parameters by simple values. The result is returned as a collection of rows which in turn have a row object with dynamic properties for each of the columns giving easy (though untyped) access to each of the fields. Likewise Execute and ExecuteNonQuery allow execution of more complex queries using similar parameter passing schemes. Note these queries use string-based queries rather than LINQ or Entity Framework’s strongly typed LINQ queries. While this may seem like a step back, it’s also in line with the expectations of non .NET script developers who are quite used to writing and using SQL strings in code rather than using OR/M frameworks. The only question is why was something not included from the beginning in .NET and Microsoft made developers build custom implementations of these basic building blocks. The implementation looks a lot like a DataTable-style data access mechanism, but to be fair, this is a common approach in scripting languages. This type of syntax that uses simple, static, data object methods to perform simple data tasks with one line of code are common in scripting languages and are a good match for folks working in PHP/Python, etc. Seems like Microsoft has taken great advantage of .NET 4.0’s dynamic typing to provide this sort of interface for row iteration where each row has properties for each field. FWIW, all the examples demonstrate using local SQL Compact files - I was unable to get a SQL Server connection string to work with the Database class (the connection string wasn’t accepted). However, since the code in the page is still plain old .NET, you can easily use standard ADO.NET code or even LINQ or Entity Framework models that are created outside of WebMatrix in separate assemblies as required. The good the bad the obnoxious - It’s still .NET The beauty (or curse depending on how you look at it :)) of Razor and the compilation model is that, behind it all, it’s still .NET. Although the syntax may look foreign, it’s still all .NET behind the scenes. You can easily access existing tools, helpers, and utilities simply by adding them to the project as references or to the bin folder. Razor automatically recognizes any assembly reference from assemblies in the bin folder. In the default configuration, Microsoft provides a host of helper functions in a Microsoft.WebPages assembly (check it out in the ASP.NET temp folder for your application), which includes a host of HTML Helpers. If you’ve used ASP.NET MVC before, a lot of the helpers should look familiar. Documentation at the moment is sketchy-there’s a very rough API reference you can check out here: http://www.asp.net/webmatrix/tutorials/asp-net-web-pages-api-reference Who needs WebMatrix? Uhm… good Question Clearly Microsoft is trying hard to create an environment with WebMatrix that is easy to use for newbie developers. The goal seems to be simplicity in providing a minimal development environment and an easy-to-use script engine/language that makes it easy to get started with. There’s also some focus on community features that can be used as starting points, such as Web Gallery applications and templates. The community features in particular are very nice and something that would be nice to eventually see in Visual Studio as well. The question is whether this is too little too late. Developers who have been clamoring for a simpler development environment on the .NET stack have mostly left for other simpler platforms like PHP or Python which are catering to the down and dirty developer. Microsoft will be hard pressed to win those folks-and other hardcore PHP developers-back. Regardless of how much you dress up a script engine fronted by the .NET Framework, it’s still the .NET Framework and all the complexity that drives it. While .NET is a fine solution in its breadth and features once you get a basic handle on the core features, the bar of entry to being productive with the .NET Framework is still pretty high. The MVC style helpers Microsoft provides are a good step in the right direction, but I suspect it’s not enough to shield new developers from having to delve much deeper into the Framework to get even basic applications built. Razor and its helpers is trying to make .NET more accessible but the reality is that in order to do useful stuff that goes beyond the handful of simple helpers you still are going to have to write some C# or VB or other .NET code. If the target is a hobby/amateur/non-programmer the learning curve isn’t made any easier by WebMatrix it’s just been shifted a tad bit further along in your development endeavor when you run out of canned components that are supplied either by Microsoft or the community. The database helpers are interesting and actually I’ve heard a lot of discussion from various developers who’ve been resisting .NET for a really long time perking up at the prospect of easier data access in .NET than the ridiculous amount of code it takes to do even simple data access with raw ADO.NET. It seems sad that such a simple concept and implementation should trigger this sort of response (especially since it’s practically trivial to create helpers like these or pick them up from countless libraries available), but there it is. It also shows that there are plenty of developers out there who are more interested in ‘getting stuff done’ easily than necessarily following the latest and greatest practices which are overkill for many development scenarios. Sometimes it seems that all of .NET is focused on the big life changing issues of development, rather than the bread and butter scenarios that many developers are interested in to get their work accomplished. And that in the end may be WebMatrix’s main raison d'être: To bring some focus back at Microsoft that simpler and more high level solutions are actually needed to appeal to the non-high end developers as well as providing the necessary tools for the high end developers who want to follow the latest and greatest trends. The current version of WebMatrix hits many sweet spots, but it also feels like it has a long way to go before it really can be a tool that a beginning developer or an accomplished developer can feel comfortable with. Although there are some really good ideas in the environment (like the gallery for downloading apps and components) which would be a great addition for Visual Studio as well, the rest of the development environment just feels like crippleware with required functionality missing especially debugging and Intellisense, but also general editor support. It’s not clear whether these are because the product is still in an early alpha release or whether it’s simply designed that way to be a really limited development environment. While simple can be good, nobody wants to feel left out when it comes to necessary tool support and WebMatrix just has that left out feeling to it. If anything WebMatrix’s technology pieces (which are really independent of the WebMatrix product) are what are interesting to developers in general. The compact IIS implementation is a nice improvement for development scenarios and SQL Compact 4.0 seems to address a lot of concerns that people have had and have complained about for some time with previous SQL Compact implementations. By far the most interesting and useful technology though seems to be the Razor view engine for its light weight implementation and it’s decoupling from the ASP.NET/HTTP pipeline to provide a standalone scripting/view engine that is pluggable. The first winner of this is going to be ASP.NET MVC which can now have a cleaner view model that isn’t inconsistent due to the baggage of non-implemented WebForms features that don’t work in MVC. But I expect that Razor will end up in many other applications as a scripting and code generation engine eventually. Visual Studio integration for Razor is currently missing, but is promised for a later release. The ASP.NET MVC team has already mentioned that Razor will eventually become the default MVC view engine, which will guarantee continued growth and development of this tool along those lines. And the Razor engine and support tools actually inherit many of the features that MVC pioneered, so there’s some synergy flowing both ways between Razor and MVC. As an existing ASP.NET developer who’s already familiar with Visual Studio and ASP.NET development, the WebMatrix IDE doesn’t give you anything that you want. The tools provided are minimal and provide nothing that you can’t get in Visual Studio today, except the minimal Razor syntax highlighting, so there’s little need to take a step back. With Visual Studio integration coming later there’s little reason to look at WebMatrix for tooling. It’s good to see that Microsoft is giving some thought about the ease of use of .NET as a platform For so many years, we’ve been piling on more and more new features without trying to take a step back and see how complicated the development/configuration/deployment process has become. Sometimes it’s good to take a step - or several steps - back and take another look and realize just how far we’ve come. WebMatrix is one of those reminders and one that likely will result in some positive changes on the platform as a whole. © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET   IIS7  

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  • Some Original Expressions

    - by Phil Factor
    Guest Editorial for Simple-Talk newsletterIn a guest editorial for the Simple-Talk Newsletter, Phil Factor wonders if we are still likely to find some more novel and unexpected ways of using the newer features of Transact SQL: or maybe in some features that have always been there! There can be a great deal of fun to be had in trying out recent features of SQL Expressions to see if  they provide new functionality.  It is surprisingly rare to find things that couldn’t be done before, but in a different   and more cumbersome way; but it is great to experiment or to read of someone else making that discovery.  One such recent feature is the ‘table value constructor’, or ‘VALUES constructor’, that managed to get into SQL Server 2008 from Standard SQL.  This allows you to create derived tables of up to 1000 rows neatly within select statements that consist of  lists of row values.  E.g. SELECT Old_Welsh, number FROM (VALUES ('Un',1),('Dou',2),('Tri',3),('Petuar',4),('Pimp',5),('Chwech',6),('Seith',7),('Wyth',8),('Nau',9),('Dec',10)) AS WelshWordsToTen (Old_Welsh, number) These values can be expressions that return single values, including, surprisingly, subqueries. You can use this device to create views, or in the USING clause of a MERGE statement. Joe Celko covered  this here and here.  It can become extraordinarily handy to use once one gets into the way of thinking in these terms, and I’ve rewritten a lot of routines to use the constructor, but the old way of using UNION can be used the same way, but is a little slower and more long-winded. The use of scalar SQL subqueries as an expression in a VALUES constructor, and then applied to a MERGE, has got me thinking. It looks very clever, but what use could one put it to? I haven’t seen anything yet that couldn’t be done almost as  simply in SQL Server 2000, but I’m hopeful that someone will come up with a way of solving a tricky problem, just in the same way that a freak of the XML syntax forever made the in-line  production of delimited lists from an expression easy, or that a weird XML pirouette could do an elegant  pivot-table rotation. It is in this sort of experimentation where the community of users can make a real contribution. The dissemination of techniques such as the Number, or Tally table, or the unconventional ways that the UPDATE statement can be used, has been rapid due to articles and blogs. However, there is plenty to be done to explore some of the less obvious features of Transact SQL. Even some of the features introduced into SQL Server 2000 are hardly well-known. Certain operations on data are still awkward to perform in Transact SQL, but we mustn’t, I think, be too ready to state that certain things can only be done in the application layer, or using a CLR routine. With the vast array of features in the product, and with the tools that surround it, I feel that there is generally a way of getting tricky things done. Or should we just stick to our lasts and push anything difficult out into procedural code? I’d love to know your views.

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  • Anatomy of a .NET Assembly - Signature encodings

    - by Simon Cooper
    If you've just joined this series, I highly recommend you read the previous posts in this series, starting here, or at least these posts, covering the CLR metadata tables. Before we look at custom attribute encoding, we first need to have a brief look at how signatures are encoded in an assembly in general. Signature types There are several types of signatures in an assembly, all of which share a common base representation, and are all stored as binary blobs in the #Blob heap, referenced by an offset from various metadata tables. The types of signatures are: Method definition and method reference signatures. Field signatures Property signatures Method local variables. These are referenced from the StandAloneSig table, which is then referenced by method body headers. Generic type specifications. These represent a particular instantiation of a generic type. Generic method specifications. Similarly, these represent a particular instantiation of a generic method. All these signatures share the same underlying mechanism to represent a type Representing a type All metadata signatures are based around the ELEMENT_TYPE structure. This assigns a number to each 'built-in' type in the framework; for example, Uint16 is 0x07, String is 0x0e, and Object is 0x1c. Byte codes are also used to indicate SzArrays, multi-dimensional arrays, custom types, and generic type and method variables. However, these require some further information. Firstly, custom types (ie not one of the built-in types). These require you to specify the 4-byte TypeDefOrRef coded token after the CLASS (0x12) or VALUETYPE (0x11) element type. This 4-byte value is stored in a compressed format before being written out to disk (for more excruciating details, you can refer to the CLI specification). SzArrays simply have the array item type after the SZARRAY byte (0x1d). Multidimensional arrays follow the ARRAY element type with a series of compressed integers indicating the number of dimensions, and the size and lower bound of each dimension. Generic variables are simply followed by the index of the generic variable they refer to. There are other additions as well, for example, a specific byte value indicates a method parameter passed by reference (BYREF), and other values indicating custom modifiers. Some examples... To demonstrate, here's a few examples and what the resulting blobs in the #Blob heap will look like. Each name in capitals corresponds to a particular byte value in the ELEMENT_TYPE or CALLCONV structure, and coded tokens to custom types are represented by the type name in curly brackets. A simple field: int intField; FIELD I4 A field of an array of a generic type parameter (assuming T is the first generic parameter of the containing type): T[] genArrayField FIELD SZARRAY VAR 0 An instance method signature (note how the number of parameters does not include the return type): instance string MyMethod(MyType, int&, bool[][]); HASTHIS DEFAULT 3 STRING CLASS {MyType} BYREF I4 SZARRAY SZARRAY BOOLEAN A generic type instantiation: MyGenericType<MyType, MyStruct> GENERICINST CLASS {MyGenericType} 2 CLASS {MyType} VALUETYPE {MyStruct} For more complicated examples, in the following C# type declaration: GenericType<T> : GenericBaseType<object[], T, GenericType<T>> { ... } the Extends field of the TypeDef for GenericType will point to a TypeSpec with the following blob: GENERICINST CLASS {GenericBaseType} 3 SZARRAY OBJECT VAR 0 GENERICINST CLASS {GenericType} 1 VAR 0 And a static generic method signature (generic parameters on types are referenced using VAR, generic parameters on methods using MVAR): TResult[] GenericMethod<TInput, TResult>( TInput, System.Converter<TInput, TOutput>); GENERIC 2 2 SZARRAY MVAR 1 MVAR 0 GENERICINST CLASS {System.Converter} 2 MVAR 0 MVAR 1 As you can see, complicated signatures are recursively built up out of quite simple building blocks to represent all the possible variations in a .NET assembly. Now we've looked at the basics of normal method signatures, in my next post I'll look at custom attribute application signatures, and how they are different to normal signatures.

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