一、問題
給了兩個(gè)各有四五十個(gè)列的表，找出他們相同的列和不同的列

二、查詢兩個(gè)表的列，存在臨時(shí)表

--#a ,#b都是臨時(shí)表，當(dāng)前連接斷開后自動(dòng)刪除
--RANK() OVER (ORDER BY syscolumns.name DESC) AS 是SQL2005支持的，在每行記錄前加上自增序號(hào)
--IDENTITY(INT,1,1) 函數(shù)必須要和into聯(lián)合使用

1、將表的列存入#a--'destTbl'比較的表名

select *  into #a from (select  RANK() OVER (ORDER BY syscolumns.name DESC) AS 序號(hào),syscolumns.name
  from syscolumns,sysobjects
    where syscolumns.[id]=sysobjects.[id]
          and sysobjects.[name]='destTbl') as t    

select * from #a

1 姓名
2 課程
3 id
4 cno

2、將表的列存入#b--'student'比較的表名

select  序號(hào)= IDENTITY(INT,1,1),syscolumns.name
    into #b  from syscolumns,sysobjects
    where syscolumns.[id]=sysobjects.[id]
          and sysobjects.[name]='student'

select * from #b

1 id
2 name
3 cno

三、分析比較各個(gè)表列的異同

用下列語句，或者稍作改動(dòng)比較
select * from #b where name in (select name from #a)
select * from #a where name not in (select name from #b)
select * from #a a, #b b where a.name=b.name
select * from #a a left join #b b on a.name=b.name