09.索引-过滤索引

USE IndexDB

GO

SELECT * INTO SalesOrderheader FROM AdventureWorks2008r2.Sales.SalesOrderheader

GO

--Unique Clustered index

CREATE UNIQUE CLUSTERED INDEX ix_SalesOrderheader ON SalesOrderheader(SalesOrderid)

GO

--Filtered Index

CREATE INDEX ix_filtered_index ON SalesOrderheader(orderdate) WHERE orderdate>‘2008-01-01‘

SELECT orderdate,SalesOrderid FROM SalesOrderheader WHERE

orderdate>‘2008-05-01‘

GO

SELECT orderdate,SalesOrderid FROM SalesOrderheader WHERE

orderdate=‘2008-03-01‘

GO

SELECT orderdate,SalesOrderid FROM SalesOrderheader WHERE

orderdate=‘2007-12-01‘

参数化查询 可能会导致过滤索引失效