select b.* from a表 as a,b表 as b where a.id=b.id and b.g>10
select * from a cross join b where b.g>10
晕 id ,c,d,e,f这几个字段你要从哪个表里面取,还是这两个表的冗余 如果是冗余 则 SELECT A.ID,B.ID,A.C,A.D,A.E,A.F,B.G FROM A INNER JOIN B ON A.C=B.C AND A.D=B.D AND A.E=B.E AND A.F=B.F WHERE B.G>10
select * from a inner join b on a.id=b.id where b.g>10
还是? select b.* from a inner join b on a.id=b.id where b.g>10
a表 和 b表的关联关系是什么?都有c、d、e、f字段,是要查询输出哪个表的这些字段?
select a.id,a.c,a.d,a.e,a.f,b.g from a a,b b where a.id=b.id and b.g>10
from a
cross join b
where b.g>10
id ,c,d,e,f这几个字段你要从哪个表里面取,还是这两个表的冗余
如果是冗余
则
SELECT A.ID,B.ID,A.C,A.D,A.E,A.F,B.G
FROM A INNER JOIN B ON A.C=B.C AND A.D=B.D AND A.E=B.E AND A.F=B.F
WHERE B.G>10
select b.*
from a
inner join b
on a.id=b.id
where b.g>10
emp_2表:有id,c,d,e,f,g从emp_1,emp_2表中查询出有id ,c,d,e,f,g的字段并且g>10