SQL> select * from a;ID NAME
---------- ----------
1 aa
2 bb
3 cc
6 dd
7 eeSQL> select * from b;ID ADDR
---------- ----------
1 aa
2 bb
3 cc
4 dd
5 eeSQL> select * from a
2 union all
3 select * from b;ID NAME
---------- ----------
1 aa
2 bb
3 cc
6 dd
7 ee
1 aa
2 bb
3 cc
4 dd
5 ee已选择10行。SQL> select * from a
2 union
3 select * from b;ID NAME
---------- ----------
1 aa
2 bb
3 cc
4 dd
5 ee
6 dd
7 ee已选择7行。SQL>
---------- ----------
1 aa
2 bb
3 cc
6 dd
7 eeSQL> select * from b;ID ADDR
---------- ----------
1 aa
2 bb
3 cc
4 dd
5 eeSQL> select * from a
2 union all
3 select * from b;ID NAME
---------- ----------
1 aa
2 bb
3 cc
6 dd
7 ee
1 aa
2 bb
3 cc
4 dd
5 ee已选择10行。SQL> select * from a
2 union
3 select * from b;ID NAME
---------- ----------
1 aa
2 bb
3 cc
4 dd
5 ee
6 dd
7 ee已选择7行。SQL>
UNION ALL
SELECT c.user_name,c.email_address FROM cpm_user c WHERE c.user_id=3这样不行,是么?