select S.SName,C.CourseID,C.Score
from Student AS S inner join Score AS C
on (S.SCode=C.StudentID)
我所要问的问题:“这两个表内联之前,是不是得建好主外键关系啊~~~~~~~~~~~”
急急急~~~~~~~~~~
from Student AS S inner join Score AS C
on (S.SCode=C.StudentID)
我所要问的问题:“这两个表内联之前,是不是得建好主外键关系啊~~~~~~~~~~~”
急急急~~~~~~~~~~
ta1 :id int,colname varchar
ta2 :id int, pid int,col varchar ta2的pid是对应 ta1的id ,两表不建立关系,但是你的数据如下时
ta1:
1,'aa'
ta2
1, 1, 'asdfaf'select b.id,a.colname ,b.col
from ta1 a
right join ta2 b on a.id = b.pid
--
1,'aa','asdfaf'