弱弱的问下inner join

[gaia_next]

select * from A inner join B on xx=xx;和select * from A,B where xx=xx;有什么区别吗 最好能举个例子说明下在复杂点的应用里的区别

[开着拖拉机泡妞]

第一种写法是属于基本的简单查询，第二种是属于连接查询，同一个查询的两种写法

[JudeHo]

效率不同啊

[勿勿]

没有区别

declare @t table (xx int,tt int)
insert into @t values(1,14)
insert into @t values(2,12)
insert into @t values(3,16)
insert into @t values(4,15)
insert into @t values(5,14)
insert into @t values(6,13)
insert into @t values(7,12)
insert into @t values(8,11)
declare @b table (xx int,tb int)
insert into @b values(1,114)
insert into @b values(2,122)
insert into @b values(3,156)
insert into @b values(4,135)
insert into @b values(5,174)
insert into @b values(6,153)
insert into @b values(7,182)
insert into @b values(8,112)
select * from @t t inner join @b b on t.xx=b.xx
select * from @t t  ,@b b where  t.xx= b.xx


(1 row(s) affected)
xx          tt          xx          tb
----------- ----------- ----------- -----------
1           14          1           114
2           12          2           122
3           16          3           156
4           15          4           135
5           14          5           174
6           13          6           153
7           12          7           182
8           11          8           112

(8 row(s) affected)

xx          tt          xx          tb
----------- ----------- ----------- -----------
1           14          1           114
2           12          2           122
3           16          3           156
4           15          4           135
5           14          5           174
6           13          6           153
7           12          7           182
8           11          8           112

(8 row(s) affected)

[电灯泡]

没区别，两种写法。