Hướng dẫn học Microsoft SQL Server 2008 part 138 pot

... calling the key lookup. If you think of SQL Server as having tables with indexes, this query execution plan appears confusing; but if you think of SQL Server as a collection of indexes with varying ... 5’s second query selected the StartDate column. Because StartDate isn’t part of the IX_WorkOrder_ProductID index, SQL Server was forced to use an evil bookmark lookup. To solve th...

Ngày tải lên: 04/07/2014, 09:20

... been using SQL Server since version 6.5. Jacob compressed his vast knowledge of SQL Server and XML into Chapter 18. Allen White, SQL Server MVP (with a minor in PowerShell), is a SQL Server Trainer ... Australian SQL Server community, and president of the Queensland SQL Server User Group. Peter is a highly regarded speaker at SQL Server events throughout Australia...

Ngày tải lên: 04/07/2014, 09:20

... minute details when desired. SQL Server is a dream system for a database developer. If there’s a theme to SQL Server 2008, it’s this: enterprise-level excellence. SQL Server 2008 opens sev- eral new ... Developing with SQL Server Part V: Data Connectivity Part VI: Enterprise Data Management Part VII: Security Part VIII: Monitoring and Auditing Part IX: Performance...

Ngày tải lên: 04/07/2014, 09:20

... world of SQL Server. The top level of the tree lists the connected servers. Object Explorer can connect to a server regardless of whether the server is known by Registered Servers. The server icon ... side. Registered Servers Registered Servers is an optional feature. If you manage only one or a few SQL Servers, then Registered Servers offers little benefit. If, however, you are res...

Ngày tải lên: 04/07/2014, 09:20

... T -SQL code. SQL Server includes dozens of functions. This section describes the functions I find most useful. Best Practice P erformance is as much a part of the data-schema design as it is a part ... computer on which the instance of SQL Server is running. The time zone offset is included. ■ ToDateTimeOffset(): Returns a DateTimeOffset type The following four SQL Server date...

Ngày tải lên: 04/07/2014, 09:20

... types: DateTime and DateTime2. DateTime2 is new to SQL Server 2008 and represents time to a much finer granularity: within 100 nanoseconds. ■ DatePart(date portion, date): Returns the ordinal number ... the complete date, only the date part being extracted: select DATEDIFF(year,’september 4 2008 ,’november 10 2009’) Result 1 select DATEDIFF(month,’september 4 2008 ,’november 10 2009’...

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... ProductCategoryID FROM dbo.ProductCategory Where ProductCategoryName = ‘Kite’); To execute this query, SQL Server first evaluates the subquery and returns a value to the outer query (your unique identifier ... Practice S QL is very flexible — there are often a dozen ways to express the same question. Your choice of SQL method should be made first according to your style and to which method...

Ngày tải lên: 04/07/2014, 09:20

... rows, then SQL Server will execute the logical equivalent of 101 queries — one for the outer query, and one subquery for every row returned by the outer query. In practice, the SQL Server Query ... 4 8 Melanie Campbell 3 12 Alysia Halloway 3 20 Grace Halloway 2 Row constructors New for SQL Server 2008, row constructors provide a convenient way to supply hard-coded values direct...

Ngày tải lên: 04/07/2014, 09:20

... query. While SQL Server 2008 s new filtered indexes are a perfect fit, it’s still a performance killer. ■ To make matters worse, because the rows still physically exist in SQL Server, and SQL Server s declarative ... dif- ferences. Ignoring for a moment the new MERGE command in SQL Server 2008, there are a few ways to code an upsert operation with T -SQL: ■ The most common meth...

Ngày tải lên: 04/07/2014, 09:20

... about the structure of the XML document. An XML document is usually described using a schema. SQL Server can generate an XML or XDR (XML Data Reduced) schema along with the query results of a FOR ... row and one column containing an NVARCHAR(MAX) value. The TYPE directive can be used to request SQL Server to return an XML data type value, instead of NVARCHAR(MAX). FOR XML queries can...

Ngày tải lên: 04/07/2014, 09:20