或用SET SHOWPLAN_TEXT 来分析语法: 示例 下例显示 SQL Server 在处理语句时如何使用索引。下面是使用索引的查询:SET SHOWPLAN_TEXT ON GO USE pubs SELECT * FROM roysched WHERE title_id = 'PS1372' GO SET SHOWPLAN_TEXT OFF GO下面是结果集:StmtText ------------------------------------------------------ USE pubsSELECT * FROM roysched WHERE title_id = 'PS1372'(2 row(s) affected)StmtText ------------------------------------------------------------------------ |--Book Lookup(BOOKMARK:([Bmk1000]), OBJECT:([pubs].[dbo].[roysched])) |--Index Seek(OBJECT:([pubs].[dbo].[roysched].[titleidind]), SEEK:([roysched].[title_id]='PS1372') ORDERED)(2 row(s) affected)下面是不使用索引的查询:SET SHOWPLAN_TEXT ON GO USE pubs SELECT * FROM roysched WHERE lorange < 5000 GO SET SHOWPLAN_TEXT OFF GO下面是结果集:StmtText ------------------------------------------------- USE pubsSELECT * FROM roysched WHERE lorange < 5000(2 row(s) affected)StmtText ------------------------------------------------------------------------ |--Table Scan(OBJECT:([pubs].[dbo].[roysched]), WHERE:([roysched].[lorange]<5000))(1 row(s) affected)
按ctrl+l进行比较
示例
下例显示 SQL Server 在处理语句时如何使用索引。下面是使用索引的查询:SET SHOWPLAN_TEXT ON
GO
USE pubs
SELECT *
FROM roysched
WHERE title_id = 'PS1372'
GO
SET SHOWPLAN_TEXT OFF
GO下面是结果集:StmtText
------------------------------------------------------
USE pubsSELECT *
FROM roysched
WHERE title_id = 'PS1372'(2 row(s) affected)StmtText
------------------------------------------------------------------------
|--Book Lookup(BOOKMARK:([Bmk1000]), OBJECT:([pubs].[dbo].[roysched]))
|--Index Seek(OBJECT:([pubs].[dbo].[roysched].[titleidind]), SEEK:([roysched].[title_id]='PS1372') ORDERED)(2 row(s) affected)下面是不使用索引的查询:SET SHOWPLAN_TEXT ON
GO
USE pubs
SELECT *
FROM roysched
WHERE lorange < 5000
GO
SET SHOWPLAN_TEXT OFF
GO下面是结果集:StmtText
-------------------------------------------------
USE pubsSELECT *
FROM roysched
WHERE lorange < 5000(2 row(s) affected)StmtText
------------------------------------------------------------------------
|--Table Scan(OBJECT:([pubs].[dbo].[roysched]), WHERE:([roysched].[lorange]<5000))(1 row(s) affected)
你写入你的SQL脚本
,再按CTRL+L看执行计划