Search Results

Search found 36773 results on 1471 pages for 'sql statement syntax'.

Page 405/1471 | < Previous Page | 401 402 403 404 405 406 407 408 409 410 411 412  | Next Page >

  • T-SQL User-Defined Functions: Ten Questions You Were Too Shy To Ask

    SQL Server User-Defined Functions are good to use in most circumstances, but there just a few questions that rarely get asked on the forums. It's a shame, because the answers to them tend to clear up some ingrained misconceptions about functions that can lead to problems, particularly with locking and performance Can 41,000 DBAs really be wrong? Join 41,000 other DBAs who are following the new series from the DBA Team: the 5 Worst Days in a DBA’s Life. Part 3, As Corrupt As It Gets, is out now – read it here.

    Read the article

  • SQL Server 2012 Integration Services - Implementing Package Security using Access Control

    SQL Server 2012 Integration Services offers a wide range of powerful features that allow you to streamline and automate tasks involving data extraction, transformation, and loading. However, incorporating these features into your existing business intelligence framework frequently necessitates additional security measures ensuring that data which is being processed remains protected from unauthorized access.

    Read the article

  • SQL Azure - Creating backups and copies of your databases

    As a DBA you always followed a practice to back up your database (or take a snapshot of your database) before making any changes so that you can revert to your old database state if something goes wrong. Also to setup a development or test environment you use a backup of your database and restore it in the respective environment. If you are moving to SQL Azure, what would you do in these cases as backup / restore and database snapshots are not supported as of now?

    Read the article

  • Using SQL Server Concatenation Efficiently

    This article shares some tips on using concatenation efficiently for application development, pointing out some things that we must consider and look at when concatenating values or fields in our queries or stored procedures. NEW! Never waste another weekend deployingDeploy SQL Server changes and ASP .NET applications fast, frequently, and without fuss, using Deployment Manager, the new tool from Red Gate. Try it now.

    Read the article

  • New SQL Monitor Custom Metric: Database Autogrowth

    This metric for Red Gate SQL Monitor measures the number of database autogrowth events (data file or log file) in the last hour. Too many autogrowth events causes disk fragmentation which requires a change in the autogrowth settings of a database. ‘Disturbing Development’Grant Fritchey & the DBA Team present the latest installment of the Top 5 hard-earned lessons of a DBA – read it now

    Read the article

  • Help us improve SQL Source Control

    We've been working really hard on SQL Source Control, and need your input. We're currently working on suggestions from our user forum and on an updated migrations feature that supports all source control systems and works across branches. We'd love it if you could spare 10 minutes to complete this survey. If you complete the survey by Friday June 14, you could win a $100 Amazon voucher. There are two up for grabs!

    Read the article

  • Simplified Restores with SQL Server 2012 Recovery Advisor

    Occasionally, a DBA may need to restore a database from a multiple backup files that originated from multiple servers. This requirement might arise, for example, in a database-mirroring configuration, where backups may be from either of the servers. Get smart with SQL Backup ProGet faster, smaller backups with integrated verification.Quickly and easily DBCC CHECKDB your backups. Learn more.

    Read the article

  • AlwaysOn Availability Groups in SQL Server 2012

    This article discusses and demonstrates AlwaysOn Availability groups in SQL Server 2012, a new feature for high availability. Keep your database and application development in syncSQL Connect is a Visual Studio add-in that brings your databases into your solution. It then makes it easy to keep your database in sync, and commit to your existing source control system. Find out more.

    Read the article

  • SharePoint 2010 Server Configuration Error -> "Cannot connect to database master"

    - by Chrish Riis
    I recieve the following error when I try to configure SharePoint 2010 Server: "Cannot connect to the database master at SQL server at [computer.domain]. The database might not exist, or the current user does not have permission to connect to it." I run the following setup: Windows Server 2008 R2 Standard with SP1 and all the updates SQL Server 2008 R2 with SP1 SharePoint Server 2010 with SP1 Everything is installed on the same server (it's a testserver) I have tried the following: Rebooting the server Checking the install account's DB rights (dbcreator, securityadmin - I even let it have sysadmin) Opened up the firewall on port 1433 and 1434 Uninstalled both SQL and SP, then reinstalled the both Enabled all client protocols in SQL Server Configuration Made sure I used the correct account for installing SharePoint (local admin) Useful links: TCP/IP settings – http:// blog.vanmeeuwen-online.nl/2010/10/cannot-connect-to-database-master-at.html http:// ybbest.wordpress.com/2011/04/22/cannot-connect-to-database-master-at-sql-server-at-sql2008r2/ Wrong slash - http:// yakimadev.com/2010/11/cannot-connect-to-database-master-at-sql-server-at-serverdbname-error-during-sharepoint-2010-products-configuration-wizard-and-installation/ Port error - http:// www.knowsharepoint.com/2011/08/error-connecting-to-database-server.html

    Read the article

  • Is ODBC on Windows 2003 slower than on Windows 7?

    - by nbolton
    I am seeing some MSSQL 2005 performance issues, and I am trying to diagnose the cause. I am using SQL profiler to gather query execution times. Both the client (using ODBC), and the SQL server are running on Windows 2003. I am also using Windows 7 (client) with a different Windows 2003 server to compare results. Windows 7 client / Windows 2003 server: SQL management studio: 393ms Through ODBC: 215ms Windows 2003 client: SQL management studio: approx 155ms Through ODBC: 3145ms ... in both cases, I'm running SQL management studio on the client. To me, these figures suggest there's something wrong with the ODBC client on the Windows 2003 server. On Windows, I see that the ODBC "SQL Server" driver is version 6.01.7600.16385 but on Windows 2003, it is 2000.86.3959.00 (by default). Could this be the problem? Is it possible to update an ODBC driver?

    Read the article

  • Cannot deploy reports on localhost/reports

    - by Jackson Sunuwar
    I am using Microsoft SQL Server 2008 R2, Sql Server Reporting Services(SSRS) on an xp virtual machine.. I have created a report and am trying to deploy it... but getting this error... The specified report server URL http://localhost/Reports could not be found. Verify the syntax of the URL and that the report server exists. I went to see my "services".... SQL Server (SQLEXPRESS) is "started", but SQL Server (MSSQLSERVER) is not. When I try to start it, it says windows could not start the sql server on local computer error code 10048 I tried to go in cmd and tried C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\Binn\sqlservr.exe -sMSSQLSERVER I get this, Server Error: 17058, Severity: 16, State: 1. can someone please help me...

    Read the article

  • Delete data from a MSSQL standby database?

    - by SQL-Newbie
    Is it possible to delete data from a read only standby database that imports shipped log files? At least in my theory this shouldn't be possible because the deletion would change the LSN and the log shipping should break. What I need is a smaller sized database than the database that ships the logs. So basically I need a way to have the (readonly) standby server storing only the most recent data. Any ideas or recommendations on this?

    Read the article

  • How would I order a table by the number of matching params in the where clause of an sql statement?

    - by Eitan
    I'm writing sql to search a database by a number of parameters. How would I go about ordering the result set by the items that match the most parameters in the where clause. For example: SELECT * FROM users WHERE username = 'eitan' OR email = '[email protected]' OR company = 'eitan' Username | email | company 1) eitan | [email protected] | blah 2) eitan | [email protected] | eitan 3) eitan | [email protected] | blah should be ordered like: 2, 3, 1. Thanks. (ps the query isn't that easy, has a lot of joins and a lot of OR's in the WHERE) Eitan

    Read the article

  • Announcing release of ASP.NET MVC 3, IIS Express, SQL CE 4, Web Farm Framework, Orchard, WebMatrix

    - by ScottGu
    I’m excited to announce the release today of several products: ASP.NET MVC 3 NuGet IIS Express 7.5 SQL Server Compact Edition 4 Web Deploy and Web Farm Framework 2.0 Orchard 1.0 WebMatrix 1.0 The above products are all free. They build upon the .NET 4 and VS 2010 release, and add a ton of additional value to ASP.NET (both Web Forms and MVC) and the Microsoft Web Server stack. ASP.NET MVC 3 Today we are shipping the final release of ASP.NET MVC 3.  You can download and install ASP.NET MVC 3 here.  The ASP.NET MVC 3 source code (released under an OSI-compliant open source license) can also optionally be downloaded here. ASP.NET MVC 3 is a significant update that brings with it a bunch of great features.  Some of the improvements include: Razor ASP.NET MVC 3 ships with a new view-engine option called “Razor” (in addition to continuing to support/enhance the existing .aspx view engine).  Razor minimizes the number of characters and keystrokes required when writing a view template, and enables a fast, fluid coding workflow. Unlike most template syntaxes, with Razor you do not need to interrupt your coding to explicitly denote the start and end of server blocks within your HTML. The Razor parser is smart enough to infer this from your code. This enables a compact and expressive syntax which is clean, fast and fun to type.  You can learn more about Razor from some of the blog posts I’ve done about it over the last 6 months Introducing Razor New @model keyword in Razor Layouts with Razor Server-Side Comments with Razor Razor’s @: and <text> syntax Implicit and Explicit code nuggets with Razor Layouts and Sections with Razor Today’s release supports full code intellisense support for Razor (both VB and C#) with Visual Studio 2010 and the free Visual Web Developer 2010 Express. JavaScript Improvements ASP.NET MVC 3 enables richer JavaScript scenarios and takes advantage of emerging HTML5 capabilities. The AJAX and Validation helpers in ASP.NET MVC 3 now use an Unobtrusive JavaScript based approach.  Unobtrusive JavaScript avoids injecting inline JavaScript into HTML, and enables cleaner separation of behavior using the new HTML 5 “data-“ attribute convention (which conveniently works on older browsers as well – including IE6). This keeps your HTML tight and clean, and makes it easier to optionally swap out or customize JS libraries.  ASP.NET MVC 3 now includes built-in support for posting JSON-based parameters from client-side JavaScript to action methods on the server.  This makes it easier to exchange data across the client and server, and build rich JavaScript front-ends.  We think this capability will be particularly useful going forward with scenarios involving client templates and data binding (including the jQuery plugins the ASP.NET team recently contributed to the jQuery project).  Previous releases of ASP.NET MVC included the core jQuery library.  ASP.NET MVC 3 also now ships the jQuery Validate plugin (which our validation helpers use for client-side validation scenarios).  We are also now shipping and including jQuery UI by default as well (which provides a rich set of client-side JavaScript UI widgets for you to use within projects). Improved Validation ASP.NET MVC 3 includes a bunch of validation enhancements that make it even easier to work with data. Client-side validation is now enabled by default with ASP.NET MVC 3 (using an onbtrusive javascript implementation).  Today’s release also includes built-in support for Remote Validation - which enables you to annotate a model class with a validation attribute that causes ASP.NET MVC to perform a remote validation call to a server method when validating input on the client. The validation features introduced within .NET 4’s System.ComponentModel.DataAnnotations namespace are now supported by ASP.NET MVC 3.  This includes support for the new IValidatableObject interface – which enables you to perform model-level validation, and allows you to provide validation error messages specific to the state of the overall model, or between two properties within the model.  ASP.NET MVC 3 also supports the improvements made to the ValidationAttribute class in .NET 4.  ValidationAttribute now supports a new IsValid overload that provides more information about the current validation context, such as what object is being validated.  This enables richer scenarios where you can validate the current value based on another property of the model.  We’ve shipped a built-in [Compare] validation attribute  with ASP.NET MVC 3 that uses this support and makes it easy out of the box to compare and validate two property values. You can use any data access API or technology with ASP.NET MVC.  This past year, though, we’ve worked closely with the .NET data team to ensure that the new EF Code First library works really well for ASP.NET MVC applications.  These two posts of mine cover the latest EF Code First preview and demonstrates how to use it with ASP.NET MVC 3 to enable easy editing of data (with end to end client+server validation support).  The final release of EF Code First will ship in the next few weeks. Today we are also publishing the first preview of a new MvcScaffolding project.  It enables you to easily scaffold ASP.NET MVC 3 Controllers and Views, and works great with EF Code-First (and is pluggable to support other data providers).  You can learn more about it – and install it via NuGet today - from Steve Sanderson’s MvcScaffolding blog post. Output Caching Previous releases of ASP.NET MVC supported output caching content at a URL or action-method level. With ASP.NET MVC V3 we are also enabling support for partial page output caching – which allows you to easily output cache regions or fragments of a response as opposed to the entire thing.  This ends up being super useful in a lot of scenarios, and enables you to dramatically reduce the work your application does on the server.  The new partial page output caching support in ASP.NET MVC 3 enables you to easily re-use cached sub-regions/fragments of a page across multiple URLs on a site.  It supports the ability to cache the content either on the web-server, or optionally cache it within a distributed cache server like Windows Server AppFabric or memcached. I’ll post some tutorials on my blog that show how to take advantage of ASP.NET MVC 3’s new output caching support for partial page scenarios in the future. Better Dependency Injection ASP.NET MVC 3 provides better support for applying Dependency Injection (DI) and integrating with Dependency Injection/IOC containers. With ASP.NET MVC 3 you no longer need to author custom ControllerFactory classes in order to enable DI with Controllers.  You can instead just register a Dependency Injection framework with ASP.NET MVC 3 and it will resolve dependencies not only for Controllers, but also for Views, Action Filters, Model Binders, Value Providers, Validation Providers, and Model Metadata Providers that you use within your application. This makes it much easier to cleanly integrate dependency injection within your projects. Other Goodies ASP.NET MVC 3 includes dozens of other nice improvements that help to both reduce the amount of code you write, and make the code you do write cleaner.  Here are just a few examples: Improved New Project dialog that makes it easy to start new ASP.NET MVC 3 projects from templates. Improved Add->View Scaffolding support that enables the generation of even cleaner view templates. New ViewBag property that uses .NET 4’s dynamic support to make it easy to pass late-bound data from Controllers to Views. Global Filters support that allows specifying cross-cutting filter attributes (like [HandleError]) across all Controllers within an app. New [AllowHtml] attribute that allows for more granular request validation when binding form posted data to models. Sessionless controller support that allows fine grained control over whether SessionState is enabled on a Controller. New ActionResult types like HttpNotFoundResult and RedirectPermanent for common HTTP scenarios. New Html.Raw() helper to indicate that output should not be HTML encoded. New Crypto helpers for salting and hashing passwords. And much, much more… Learn More about ASP.NET MVC 3 We will be posting lots of tutorials and samples on the http://asp.net/mvc site in the weeks ahead.  Below are two good ASP.NET MVC 3 tutorials available on the site today: Build your First ASP.NET MVC 3 Application: VB and C# Building the ASP.NET MVC 3 Music Store We’ll post additional ASP.NET MVC 3 tutorials and videos on the http://asp.net/mvc site in the future. Visit it regularly to find new tutorials as they are published. How to Upgrade Existing Projects ASP.NET MVC 3 is compatible with ASP.NET MVC 2 – which means it should be easy to update existing MVC projects to ASP.NET MVC 3.  The new features in ASP.NET MVC 3 build on top of the foundational work we’ve already done with the MVC 1 and MVC 2 releases – which means that the skills, knowledge, libraries, and books you’ve acquired are all directly applicable with the MVC 3 release.  MVC 3 adds new features and capabilities – it doesn’t obsolete existing ones. You can upgrade existing ASP.NET MVC 2 projects by following the manual upgrade steps in the release notes.  Alternatively, you can use this automated ASP.NET MVC 3 upgrade tool to easily update your  existing projects. Localized Builds Today’s ASP.NET MVC 3 release is available in English.  We will be releasing localized versions of ASP.NET MVC 3 (in 9 languages) in a few days.  I’ll blog pointers to the localized downloads once they are available. NuGet Today we are also shipping NuGet – a free, open source, package manager that makes it easy for you to find, install, and use open source libraries in your projects. It works with all .NET project types (including ASP.NET Web Forms, ASP.NET MVC, WPF, WinForms, Silverlight, and Class Libraries).  You can download and install it here. NuGet enables developers who maintain open source projects (for example, .NET projects like Moq, NHibernate, Ninject, StructureMap, NUnit, Windsor, Raven, Elmah, etc) to package up their libraries and register them with an online gallery/catalog that is searchable.  The client-side NuGet tools – which include full Visual Studio integration – make it trivial for any .NET developer who wants to use one of these libraries to easily find and install it within the project they are working on. NuGet handles dependency management between libraries (for example: library1 depends on library2). It also makes it easy to update (and optionally remove) libraries from your projects later. It supports updating web.config files (if a package needs configuration settings). It also allows packages to add PowerShell scripts to a project (for example: scaffold commands). Importantly, NuGet is transparent and clean – and does not install anything at the system level. Instead it is focused on making it easy to manage libraries you use with your projects. Our goal with NuGet is to make it as simple as possible to integrate open source libraries within .NET projects.  NuGet Gallery This week we also launched a beta version of the http://nuget.org web-site – which allows anyone to easily search and browse an online gallery of open source packages available via NuGet.  The site also now allows developers to optionally submit new packages that they wish to share with others.  You can learn more about how to create and share a package here. There are hundreds of open-source .NET projects already within the NuGet Gallery today.  We hope to have thousands there in the future. IIS Express 7.5 Today we are also shipping IIS Express 7.5.  IIS Express is a free version of IIS 7.5 that is optimized for developer scenarios.  It works for both ASP.NET Web Forms and ASP.NET MVC project types. We think IIS Express combines the ease of use of the ASP.NET Web Server (aka Cassini) currently built-into Visual Studio today with the full power of IIS.  Specifically: It’s lightweight and easy to install (less than 5Mb download and a quick install) It does not require an administrator account to run/debug applications from Visual Studio It enables a full web-server feature set – including SSL, URL Rewrite, and other IIS 7.x modules It supports and enables the same extensibility model and web.config file settings that IIS 7.x support It can be installed side-by-side with the full IIS web server as well as the ASP.NET Development Server (they do not conflict at all) It works on Windows XP and higher operating systems – giving you a full IIS 7.x developer feature-set on all Windows OS platforms IIS Express (like the ASP.NET Development Server) can be quickly launched to run a site from a directory on disk.  It does not require any registration/configuration steps. This makes it really easy to launch and run for development scenarios.  You can also optionally redistribute IIS Express with your own applications if you want a lightweight web-server.  The standard IIS Express EULA now includes redistributable rights. Visual Studio 2010 SP1 adds support for IIS Express.  Read my VS 2010 SP1 and IIS Express blog post to learn more about what it enables.  SQL Server Compact Edition 4 Today we are also shipping SQL Server Compact Edition 4 (aka SQL CE 4).  SQL CE is a free, embedded, database engine that enables easy database storage. No Database Installation Required SQL CE does not require you to run a setup or install a database server in order to use it.  You can simply copy the SQL CE binaries into the \bin directory of your ASP.NET application, and then your web application can use it as a database engine.  No setup or extra security permissions are required for it to run. You do not need to have an administrator account on the machine. Just copy your web application onto any server and it will work. This is true even of medium-trust applications running in a web hosting environment. SQL CE runs in-memory within your ASP.NET application and will start-up when you first access a SQL CE database, and will automatically shutdown when your application is unloaded.  SQL CE databases are stored as files that live within the \App_Data folder of your ASP.NET Applications. Works with Existing Data APIs SQL CE 4 works with existing .NET-based data APIs, and supports a SQL Server compatible query syntax.  This means you can use existing data APIs like ADO.NET, as well as use higher-level ORMs like Entity Framework and NHibernate with SQL CE.  This enables you to use the same data programming skills and data APIs you know today. Supports Development, Testing and Production Scenarios SQL CE can be used for development scenarios, testing scenarios, and light production usage scenarios.  With the SQL CE 4 release we’ve done the engineering work to ensure that SQL CE won’t crash or deadlock when used in a multi-threaded server scenario (like ASP.NET).  This is a big change from previous releases of SQL CE – which were designed for client-only scenarios and which explicitly blocked running in web-server environments.  Starting with SQL CE 4 you can use it in a web-server as well. There are no license restrictions with SQL CE.  It is also totally free. Tooling Support with VS 2010 SP1 Visual Studio 2010 SP1 adds support for SQL CE 4 and ASP.NET Projects.  Read my VS 2010 SP1 and SQL CE 4 blog post to learn more about what it enables.  Web Deploy and Web Farm Framework 2.0 Today we are also releasing Microsoft Web Deploy V2 and Microsoft Web Farm Framework V2.  These services provide a flexible and powerful way to deploy ASP.NET applications onto either a single server, or across a web farm of machines. You can learn more about these capabilities from my previous blog posts on them: Introducing the Microsoft Web Farm Framework Automating Deployment with Microsoft Web Deploy Visit the http://iis.net website to learn more and install them. Both are free. Orchard 1.0 Today we are also releasing Orchard v1.0.  Orchard is a free, open source, community based project.  It provides Content Management System (CMS) and Blogging System support out of the box, and makes it possible to easily create and manage web-sites without having to write code (site owners can customize a site through the browser-based editing tools built-into Orchard).  Read these tutorials to learn more about how you can setup and manage your own Orchard site. Orchard itself is built as an ASP.NET MVC 3 application using Razor view templates (and by default uses SQL CE 4 for data storage).  Developers wishing to extend an Orchard site with custom functionality can open and edit it as a Visual Studio project – and add new ASP.NET MVC Controllers/Views to it.  WebMatrix 1.0 WebMatrix is a new, free, web development tool from Microsoft that provides a suite of technologies that make it easier to enable website development.  It enables a developer to start a new site by browsing and downloading an app template from an online gallery of web applications (which includes popular apps like Umbraco, DotNetNuke, Orchard, WordPress, Drupal and Joomla).  Alternatively it also enables developers to create and code web sites from scratch. WebMatrix is task focused and helps guide developers as they work on sites.  WebMatrix includes IIS Express, SQL CE 4, and ASP.NET - providing an integrated web-server, database and programming framework combination.  It also includes built-in web publishing support which makes it easy to find and deploy sites to web hosting providers. You can learn more about WebMatrix from my Introducing WebMatrix blog post this summer.  Visit http://microsoft.com/web to download and install it today. Summary I’m really excited about today’s releases – they provide a bunch of additional value that makes web development with ASP.NET, Visual Studio and the Microsoft Web Server a lot better.  A lot of folks worked hard to share this with you today. On behalf of my whole team – we hope you enjoy them! Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

    Read the article

  • More SQL Smells

    - by Nick Harrison
    Let's continue exploring some of the SQL Smells from Phil's list. He has been putting together. Datatype mis-matches in predicates that rely on implicit conversion.(Plamen Ratchev) This is a great example poking holes in the whole theory of "If it works it's not broken" Queries will this probably will generally work and give the correct response. In fact, without careful analysis, you probably may be completely oblivious that there is even a problem. This subtle little problem will needlessly complicate queries and slow them down regardless of the indexes applied. Consider this example: CREATE TABLE [dbo].[Page](     [PageId] [int] IDENTITY(1,1) NOT NULL,     [Title] [varchar](75) NOT NULL,     [Sequence] [int] NOT NULL,     [ThemeId] [int] NOT NULL,     [CustomCss] [text] NOT NULL,     [CustomScript] [text] NOT NULL,     [PageGroupId] [int] NOT NULL;  CREATE PROCEDURE PageSelectBySequence ( @sequenceMin smallint , @sequenceMax smallint ) AS BEGIN SELECT [PageId] , [Title] , [Sequence] , [ThemeId] , [CustomCss] , [CustomScript] , [PageGroupId] FROM [CMS].[dbo].[Page] WHERE Sequence BETWEEN @sequenceMin AND @SequenceMax END  Note that the Sequence column is defined as int while the sequence parameter is defined as a small int. The problem is that the database may have to do a lot of type conversions to evaluate the query. In some cases, this may even negate the indexes that you have in place. Using Correlated subqueries instead of a join   (Dave_Levy/ Plamen Ratchev) There are two main problems here. The first is a little subjective, since this is a non-standard way of expressing the query, it is harder to understand. The other problem is much more objective and potentially problematic. You are taking much of the control away from the optimizer. Written properly, such a query may well out perform a corresponding query written with traditional joins. More likely than not, performance will degrade. Whenever you assume that you know better than the optimizer, you will most likely be wrong. This is the fundmental problem with any hint. Consider a query like this:  SELECT Page.Title , Page.Sequence , Page.ThemeId , Page.CustomCss , Page.CustomScript , PageEffectParams.Name , PageEffectParams.Value , ( SELECT EffectName FROM dbo.Effect WHERE EffectId = dbo.PageEffects.EffectId ) AS EffectName FROM Page INNER JOIN PageEffect ON Page.PageId = PageEffects.PageId INNER JOIN PageEffectParam ON PageEffects.PageEffectId = PageEffectParams.PageEffectId  This can and should be written as:  SELECT Page.Title , Page.Sequence , Page.ThemeId , Page.CustomCss , Page.CustomScript , PageEffectParams.Name , PageEffectParams.Value , EffectName FROM Page INNER JOIN PageEffect ON Page.PageId = PageEffects.PageId INNER JOIN PageEffectParam ON PageEffects.PageEffectId = PageEffectParams.PageEffectId INNER JOIN dbo.Effect ON dbo.Effects.EffectId = dbo.PageEffects.EffectId  The correlated query may just as easily show up in the where clause. It's not a good idea in the select clause or the where clause. Few or No comments. This one is a bit more complicated and controversial. All comments are not created equal. Some comments are helpful and need to be included. Other comments are not necessary and may indicate a problem. I tend to follow the rule of thumb that comments that explain why are good. Comments that explain how are bad. Many people may be shocked to hear the idea of a bad comment, but hear me out. If a comment is needed to explain what is going on or how it works, the logic is too complex and needs to be simplified. Comments that explain why are good. Comments may explain why the sql is needed are good. Comments that explain where the sql is used are good. Comments that explain how tables are related should not be needed if the sql is well written. If they are needed, you need to consider reworking the sql or simplify your data model. Use of functions in a WHERE clause. (Anil Das) Calling a function in the where clause will often negate the indexing strategy. The function will be called for every record considered. This will often a force a full table scan on the tables affected. Calling a function will not guarantee that there is a full table scan, but there is a good chance that it will. If you find that you often need to write queries using a particular function, you may need to add a column to the table that has the function already applied.

    Read the article

  • SQL Constraints &ndash; CHECK and NOCHECK

    - by David Turner
    One performance issue i faced at a recent project was with the way that our constraints were being managed, we were using Subsonic as our ORM, and it has a useful tool for generating your ORM code called SubStage – once configured, you can regenerate your DAL code easily based on your database schema, and it can even be integrated into your build as a pre-build event if you want to do this.  SubStage also offers the useful feature of being able to generate DDL scripts for your entire database, and can script your data for you too. The problem came when we decided to use the generate scripts feature to migrate the database onto a test database instance – it turns out that the DDL scripts that it generates include the WITH NOCHECK option, so when we executed them on the test instance, and performed some testing, we found that performance wasn’t as expected. A constraint can be disabled, enabled but not trusted, or enabled and trusted.  When it is disabled, data can be inserted that violates the constraint because it is not being enforced, this is useful for bulk load scenarios where performance is important.  So what does it mean to say that a constraint is trusted or not trusted?  Well this refers to the SQL Server Query Optimizer, and whether it trusts that the constraint is valid.  If it trusts the constraint then it doesn’t check it is valid when executing a query, so the query can be executed much faster. Here is an example base in this article on TechNet, here we create two tables with a Foreign Key constraint between them, and add a single row to each.  We then query the tables: 1 DROP TABLE t2 2 DROP TABLE t1 3 GO 4 5 CREATE TABLE t1(col1 int NOT NULL PRIMARY KEY) 6 CREATE TABLE t2(col1 int NOT NULL) 7 8 ALTER TABLE t2 WITH CHECK ADD CONSTRAINT fk_t2_t1 FOREIGN KEY(col1) 9 REFERENCES t1(col1) 10 11 INSERT INTO t1 VALUES(1) 12 INSERT INTO t2 VALUES(1) 13 GO14 15 SELECT COUNT(*) FROM t2 16 WHERE EXISTS17 (SELECT *18 FROM t1 19 WHERE t1.col1 = t2.col1) This all works fine, and in this scenario the constraint is enabled and trusted.  We can verify this by executing the following SQL to query the ‘is_disabled’ and ‘is_not_trusted’ properties: 1 select name, is_disabled, is_not_trusted from sys.foreign_keys This gives the following result: We can disable the constraint using this SQL: 1 alter table t2 NOCHECK CONSTRAINT fk_t2_t1 And when we query the constraints again, we see that the constraint is disabled and not trusted: So the constraint won’t be enforced and we can insert data into the table t2 that doesn’t match the data in t1, but we don’t want to do this, so we can enable the constraint again using this SQL: 1 alter table t2 CHECK CONSTRAINT fk_t2_t1 But when we query the constraints again, we see that the constraint is enabled, but it is still not trusted: This means that the optimizer will check the constraint each time a query is executed over it, which will impact the performance of the query, and this is definitely not what we want, so we need to make the constraint trusted by the optimizer again.  First we should check that our constraints haven’t been violated, which we can do by running DBCC: 1 DBCC CHECKCONSTRAINTS (t2) Hopefully you see the following message indicating that DBCC completed without finding any violations of your constraint: Having verified that the constraint was not violated while it was disabled, we can simply execute the following SQL:   1 alter table t2 WITH CHECK CHECK CONSTRAINT fk_t2_t1 At first glance this looks like it must be a typo to have the keyword CHECK repeated twice in succession, but it is the correct syntax and when we query the constraints properties, we find that it is now trusted again: To fix our specific problem, we created a script that checked all constraints on our tables, using the following syntax: 1 ALTER TABLE t2 WITH CHECK CHECK CONSTRAINT ALL

    Read the article

  • Backup SQL Database Federation

    - by Herve Roggero
    One of the amazing features of Windows Azure SQL Database is the ability to create federations in order to scale your cloud databases. However until now, there were very few options available to backup federated databases. In this post I will show you how Enzo Cloud Backup can help you backup, and restore your federated database easily. You can restore federated databases in SQL Database, or even on SQL Server (as regular databases). Generally speaking, you will need to perform the following steps to backup and restore the federations of a SQL Database: Backup the federation root Backup the federation members Restore the federation root Restore the federation members These actions can be automated using: the built-in scheduler of Enzo Cloud Backup, the command-line utilities, or the .NET Cloud Backup API provided, giving you complete control on how you want to perform your backup and restore operations. Backing up federations Let’s look at the tool to backup federations. You can explore your existing federations by using the Enzo Cloud Backup application as shown below. As you can see, the federation root and the various federations available are shown in separate tabs for convenience. You would first need to backup the federation root (unless you intend to restore the federation member on a local SQL Server database and you don’t need what’s in the federation root). The steps are similar than those to backup a federation member, so let’s proceed to backing up a federation member. You can click on a specific federation member to view the database details by clicking at the tab that contains your federation member. You can see the size currently consumed and a summary of its content at the bottom of the screen. If you right-click on a specific range, you can choose to backup the federation member. This brings up a window with the details of the federation member already filled out for you, including the value of the member that is used to select the federation member. Notice that the list of Federations includes “Federation Root”, which is what you need to select to backup the federation root (you can also do that directly from the root database tab).  Once you provide at least one backup destination, you can begin the backup operation.  From this window, you can also schedule this operation as a job and perform this operation entirely in the cloud. You can also “filter” the connection, so that only the specific member value is backed up (this will backup all the global tables, and only the records for which the distribution value is the one specified). You can repeat this operation for every federation member in your federation. Restoring Federations Once backed up, you can restore your federations easily. Select the backup device using the tool, then select Restore. The following window will appear. From here you can create a new root database. You can also view the backup properties, showing you exactly which federations will be created. Under the Federations tab, you can select how the federations will be created. I chose to recreate the federations and let the tool perform all the SPLIT operations necessary to recreate the same number of federation members. Other options include to create the first federation member only, or not to create the federation members at all. Once the root database has been restored and the federation members have been created, you can restore the federation members you previously backed up. The screen below shows you how to restore a backup of a federation member into a specific federation member (the details of the federation member are provided to make it easier to identify). Conclusion This post gave you an overview on how to backup and restore federation roots and federation members. The backup operations can be setup once, then scheduled daily.

    Read the article

  • Ideas on C# DSL syntax

    - by Dmitriy Nagirnyak
    Hi, I am thinking about implementing a templating engine using only the plain C#/.NET 4 syntax with the benefit of static typing. Then on top of that templating language we could create Domain Specific Languages (let's say HTML4, XHTML, HTML5, RSS, Atom, Multipart Emails and so on). One of the best DSLs in .NET 4 (if not only one) is SharpDOM. It implements HTML-specific DSL. Looking at SharpDOM, I am really impressed of what you can do using .NET (4). So I believe there are some not-so-well-known ways for implementing custom DSLs in .NET 4. Possibly not as well as in Ruby, but still. So my the question would be: what are the C# (4) specific syntax features that can be used for implementing custom DSLs? Examples I can think of right now: // HTML - doesn't look tooo readable :) div(clas: "head", ul(clas: "menu", id: "main-menu", () => { foreach(var item in allItems) { li(item.Name) } }) // See how much noise it has with all the closing brackets? ) // Plain text (Email or something) - probably too simple Line("Dear {0}", user.Name); Line("You have been kicked off from this site"); For me it is really hard to come up with the syntax with least amount of noise. Please NOTE that I am not talking about another language (Boo, IronRuby etc), neither I am not talking about different templating engines (NHaml, Spark, StringTemplate etc). Thanks, Dmitriy.

    Read the article

  • Composite key syntax in Boost MultiIndex

    - by Sarah
    Even after studying the examples, I'm having trouble figuring out how to extract ranges using a composite key on a MultiIndex container. typedef multi_index_container< boost::shared_ptr< Host >, indexed_by< hashed_unique< const_mem_fun<Host,int,&Host::getID> >, // ID index ordered_non_unique< const_mem_fun<Host,int,&Host::getAgeInY> >, // Age index ordered_non_unique< const_mem_fun<Host,int,&Host::getHousehold> >, // Household index ordered_non_unique< // Age & eligibility status index composite_key< Host, const_mem_fun<Host,int,&Host::getAgeInY>, const_mem_fun<Host,bool,&Host::isPaired> > > > // end indexed_by > HostContainer; My goal is to get an iterator pointing to the first of the subset of elements in HostContainer hmap that has age partnerAge and returns false to Host::isPaired(): std::pair< hmap::iterator,hmap::iterator > pit = hmap.equal_range(boost::make_tuple( partnerAge, false ) ); I think this is very wrong. How/Where do I specify the iterator index (which should be 3 for age & eligibility)? I will include other composite keys in the future. What exactly are the two iterators in std::pair? (I'm copying syntax from an example that I don't understand.) I would ideally use std::count to calculate the number of elements of age partnerAge that are eligible (return false to Host::isPaired()). What is the syntax for extracting the sorted index that meets these requirements? I'm obviously still learning C++ syntax. Thanks in advance for any help.

    Read the article

< Previous Page | 401 402 403 404 405 406 407 408 409 410 411 412  | Next Page >