| 50、关于JOBCN现在查询分页的新方法(如下),用性能优化器分析性能的瓶颈,假如在I/O或者网络的速度上,如下的方法优化切实有效,假如在CPU或者内存上,用现在的方法更好。请区分如下的方法,说明索引越小越好。 begin DECLARE @local_variable table (FID int identity(1,1),ReferenceID varchar(20)) insert into @local_variable (ReferenceID) select top 100000 ReferenceID from chineseresume order by ReferenceID select * from @local_variable where Fid > 40 and fid <= 60 end 和 begin DECLARE @local_variable table (FID int identity(1,1),ReferenceID varchar(20)) insert into @local_variable (ReferenceID) select top 100000 ReferenceID from chineseresume order by updatedate select * from @local_variable where Fid > 40 and fid <= 60 end 的不同 begin create table #temp (FID int identity(1,1),ReferenceID varchar(20)) insert into #temp (ReferenceID) select top 100000 ReferenceID from chineseresume order by updatedate select * from #temp where Fid > 40 and fid <= 60 drop table #temp end
|
| 共6页: 上一页 [1] [2] [3] [4] [5] 6 下一页 |
评论加载中…