hcw_peter的专栏

if exists (select 1 from sysobjects where name = sp_spaceused2 and type = P)begin    drop procedure sp_spaceused2endgo create procedure sp_spaceused2 (    @type varchar(2) = U, --

SET STATISTICS PROFILE ON select * from t1 where id=001 SET STATISTICS PROFILE OFF －－－－－－－－－－－执行后能看到有层次结构的检索结构－－－－－－－－－－－SELECT * FROM [t1] WHERE [id]=@1  |--Nested Loops(Inner Join, OUTER REF