有Ta表,和Tb表,其结构如下
Ta
IDa,IDb,IDc
1 2 3
2 2 1
Tb
ID Name
1 sluger
2 John
3 smith
要求结果selcet之后如下:
IDa IDb IDc
----------------
sluger john smith
john john sluger
----------------
就是将Ta表中的代号,转成Tb表中的姓名我的做法是三次join,不知道这样做对不对?还有其他方法吗?
Ta
IDa,IDb,IDc
1 2 3
2 2 1
Tb
ID Name
1 sluger
2 John
3 smith
要求结果selcet之后如下:
IDa IDb IDc
----------------
sluger john smith
john john sluger
----------------
就是将Ta表中的代号,转成Tb表中的姓名我的做法是三次join,不知道这样做对不对?还有其他方法吗?
select b.name as IDa,c.name as IDb,d.name as IDc
from Ta a
left join Tb b on a.IDa=b.ID
left join Tb b on a.IDb=b.ID
left join Tb b on a.IDc=b.ID估计你写的跟我一样,呵呵
(SELECT Name FROM Tb WHERE Tb.ID = Ta.IDa) AS IDa,
(SELECT Name FROM Tb WHERE Tb.ID = Ta.IDb) AS IDb,
(SELECT Name FROM Tb WHERE Tb.ID = Ta.IDc) AS IDc
FROM Ta这个好不好不知道
对不对也不知道
left join Tb b on a.IDb=b.ID
left join Tb b on a.IDc=b.ID
打错了吧!