表A,字段ID_A,NAME_A;
表B,字段ID_B,NAME_B,ID_A,ID_C;
表C,字段ID_C,NAME_C;
要求用一条语句查询出B表的所有记录,并将字段ID_A关联到A表的NAME_A,ID_C关联到表C的NAME_C;
输出ID_B,NAME_B,NAME_A,NAME_C;
表B,字段ID_B,NAME_B,ID_A,ID_C;
表C,字段ID_C,NAME_C;
要求用一条语句查询出B表的所有记录,并将字段ID_A关联到A表的NAME_A,ID_C关联到表C的NAME_C;
输出ID_B,NAME_B,NAME_A,NAME_C;
from A,B,C
where a.ID_A=b.ID_A and b.ID_C=c.ID_C
from A,B,C
where a.ID_A=b.ID_A and b.ID_C=c.ID_C
表B,字段ID_B,NAME_B,ID_A,ID_C;
表C,字段ID_C,NAME_C;
要求用一条语句查询出B表的所有记录,并将字段ID_A关联到A表的NAME_A,ID_C关联到表C的NAME_C;
输出ID_B,NAME_B,NAME_A,NAME_C;select id_b,name_b,name_a ,name_c from 表b a left join 表a b
on a.id_a=b.id_a left join 表c c
on a.id_c_c.id_c
select ID_B,NAME_B,NAME_A,NAME_C
from A,B,C
where a.ID_A=b.ID_A and b.ID_C=c.ID_C
from A,B,C
where a.ID_A=b.ID_A and b.ID_C=c.ID_C
on a.id_a=b.id_a left join 表c c
on a.id_c=c.id_c
select ID_B,NAME_B,NAME_A,NAME_C
from A join B on A.ID_A=B.ID_A join C
on B.ID_C=C.ID_C
where a.ID_A=b.ID_A and b.ID_C=c.ID_C
b.id_b ,
b.name_b ,
(select name_a from a where id_a = b.id_a),
(select name_c from a where id_c = b.id_c)
from b