数据库查询问题 在线等
table1有字段A，B，
table2有字段C，D
select a,b from table1 where a = 1
select c,d from table2 where c =2
这两条语句能不能写在一条查询语句里 做为一个结果集合返回
[解决办法]
(select a,b from table1 where a = 1)
union
(select c as a,d as b from table2 where c =2)
[解决办法]
如果
table1有字段A，和 table2有字段C
table1有字段B，和 table2有字段D
类型是一致.
这样就可以了
select a,b from table1 where a = 1
union all
select c,d from table2 where c =2
