建立表:
CREATE TABLE [TestTable] ( ?[ID] [int] IDENTITY (1,1) NOT NULL, ?[FirstName] [nvarchar] (100) COLLATE Chinese_PRC_CI_AS NULL, ?[LastName] [nvarchar] (100) COLLATE Chinese_PRC_CI_AS NULL, ?[Country] [nvarchar] (50) COLLATE Chinese_PRC_CI_AS NULL, ?[Note] [nvarchar] (2000) COLLATE Chinese_PRC_CI_AS NULL? ) ON [PRIMARY] GO
?
插入数据:(2万条,用更多的数据测试会明显一些) SET IDENTITY_INSERT TestTable ON
declare @i int set @i=1 while @i<=20000 begin ??? insert into TestTable([id],FirstName,LastName,Country,Note) values(@i,'FirstName_XXX','LastName_XXX','Country_XXX','Note_XXX') ??? set @i=@i+1 end
SET IDENTITY_INSERT TestTable OFF
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分页方案一:(利用Not In和SELECT TOP分页) 语句形式: SELECT TOP 10 * FROM TestTable WHERE (ID NOT IN ????????? (SELECT TOP 20 id ???????? FROM TestTable ???????? ORDER BY id)) ORDER BY ID
SELECT TOP 页大小 * FROM TestTable WHERE (ID NOT IN ????????? (SELECT TOP 页大小*页数 id ???????? FROM 表 ???????? ORDER BY id)) ORDER BY ID
分页方案二:(利用ID大于多少和SELECT TOP分页) 语句形式: SELECT TOP 10 * FROM TestTable WHERE (ID > ????????? (SELECT MAX(id) ???????? FROM (SELECT TOP 20 id ???????????????? FROM TestTable ???????????????? ORDER BY id) AS T)) ORDER BY ID
SELECT TOP 页大小 * FROM TestTable WHERE (ID > ????????? (SELECT MAX(id) ???????? FROM (SELECT TOP 页大小*页数 id ???????????????? FROM 表 ???????????????? ORDER BY id) AS T)) ORDER BY ID
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分页方案三:(利用SQL的游标存储过程分页) create? procedure XiaoZhengGe @sqlstr nvarchar(4000),--查询字符串 @currentpage int,?--第N页 @pagesize int?--每页行数 as set nocount on declare @P1 int,?--P1是游标的id ?@rowcount int exec sp_cursoropen @P1 output,@sqlstr,@scrollopt=1,@ccopt=1,@rowcount=@rowcount output select ceiling(1.0*@rowcount/@pagesize) as 总页数--,@rowcount as 总行数,@currentpage as 当前页? set @currentpage=(@currentpage-1)*@pagesize+1 exec sp_cursorfetch @P1,16,@currentpage,@pagesize? exec sp_cursorclose @P1 set nocount off
其它的方案:如果没有主键,可以用临时表,也可以用方案三做,但是效率会低。 建议优化的时候,加上主键和索引,查询效率会提高。
通过SQL 查询分析器,显示比较:我的结论是: 分页方案二:(利用ID大于多少和SELECT TOP分页)效率最高,需要拼接SQL语句 分页方案一:(利用Not In和SELECT TOP分页)?? 效率次之,需要拼接SQL语句 分页方案三:(利用SQL的游标存储过程分页)??? 效率最差,但是最为通用
在实际情况中,要具体分析。?
(编辑:李大同)
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