| SQL Server 2005相对于SQL Server 2000改进很大,有些还是非常实用的。 举几个例子来简单说明 这些例子我引用了Northwind库。 1. TOP 表达式 SQL Server 2000的TOP是个固定值,是不是觉得不爽,现在改进了。
 --前n名的订单declare @n int
 set @n = 10
 select TOP(@n) * from Orders
 2. 分页 不知各位过去用SQL Server 2000是怎么分页的,大多都用到了临时表。SQL Server 2005一句话就支持分页,性能据说也非常不错。
 --按Freight从小到大排序,求20到30行的结果
 select * from(
 select OrderId, Freight, ROW_NUMBER() OVER(order by Freight) as row from Orders
 ) a
 where row between 20 and 30
 3. 排名  select * from(
 select OrderId, Freight, RANK() OVER(order by Freight) as rank from Orders
 ) a
 where rank between 20 and 30
 4. try ... catch SQL Server 2000没有异常,T-SQL必须逐行检查错误代码,对于习惯了try catch程序员,2005是不是更加亲切:
 SET XACT_ABORT ON  -- 打开 try功能
 BEGIN TRY
 begin tran
 insert into Orders(CustomerId) values(-1)
 commit tran
 print 'commited'
 END TRY
 BEGIN CATCH
 rollback
 print 'rolled back'
 END CATCH
 5. 通用表达式CTE 通过表达式可免除你过去创建临时表的麻烦。
 www.knowsky.com
 --例子:结合通用表达式进行分页
 WITH OrderFreight AS(
 select OrderId, Freight, ROW_NUMBER() OVER(order by Freight) as row from Orders
 )
 select OrderId, Freight from OrderFreight where row between 10 and 20
 特别,通过表达式还支持递归。
 6. 直接发布Web Service
 想要把store procedure变成Web Service就用这个吧,.NET, IIS都不需要,通过Windows 2003的HTTP Protocol Stack直接发布WebService,用这个功能需要Windows 2003 sp1
 --DataSet CustOrdersOrders(string customerID)  CREATE ENDPOINT Orders_Endpoint
 state=started
 as http(
 path='/sql/orders',
 AUTHENTICATION=(INTEGRATED),
 ports=(clear)
 )
 for soap(
 WebMethod 'CustOrdersOrders'(
 name='Northwind.dbo.CustOrdersOrders'
 ),
 
 wsdl=default,
 database='Northwind',
 namespace='http://mysite.org/'
 )
 Web Service就发布好了,敲入http://localhost/sql/orders?wsdl得到wsdl
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