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  • sql 几种分页方法的性能对比

    create database DBTest
    
    
    use DBTest--创建测试表
    
    create table pagetest
    (id int identity(1,1) not null,
    col01 int null,
    col02 nvarchar(50) null,
    col03 datetime null)
    
    --1000万记录集 
    
    delete from pagetest
    
    declare @i int
    set @i=0
    while(@i<10000000)
    begin
    insert into pagetest 
    select cast(floor(rand()*10000) as int),left(newid(),10),getdate()    
    set @i=@i+1
    end 
    
    --数据库没插入那么多只插入了4005805 条 测试结果 
    
    
    
    
    
    
    --设定开始和结束的时间,页大小 和 页
    declare @begin_date datetime,@end_date datetime declare @pagesize int ,@curPage int declare @strSql varchar(800) set @pagesize=50 set @curPage=78000 --第万页的数据 select @begin_date = getdate() --用top not in --set @strSql='select top '+ cast(@pagesize as varchar(50))+' * from pagetest where --id not in (select top '+Cast(@pagesize*(@curPage-1) as varchar(50)) +' id from pagetest)' --exec(@strSql)
    --用not exists
    
    --select top  50 * from pagetest where 
    --not exists (select 1 from (select top (50*78000) id from pagetest) as a where a.id =pagetest.id )
    --order by id 
     
    --用max、top
    --select top 50 * from pagetest 
    --where id >(select max(id) from (select top (50*78000) id  from pagetest) as a)
    --order by id 
     
    -- 用row_number 
    --select top 50 * from
    --(select row_number()over(order by id) rid,* from pagetest) as tbTemp
    --where rid>(50*78000)
     
    --select * from (select row_number()over(order by id) rid,* from pagetest) as tbTemp
    --where rid>50*78000 and rid<=(50*(78000+1))
     
    --select * from (select row_number()over(order by id) rid,* from pagetest) as tbTemp
    --where  rid between 50*78000 and 50*(78000+1)
    
    
     
    --csdn 的另外的一种方法
    select * from (
    select row_number()over(order by rowcol) rid,*
                     from (select top (50*(78000+1)) rowcol=0,* from dbo.pagetest order by id ) 
                     as a
                ) as b 
    where b.rid >50*78000
    
     
    select @end_date = getdate()
    select datediff(ms,@begin_date,@end_date) as '毫秒'
    
    
    
    
    
    
    在同样400万条数据中,用max .top  这种方法是最快的
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  • 原文地址:https://www.cnblogs.com/hzy168/p/3048860.html
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