mysql> select b.n as n from ta,(select name n from ta) b where b.n="name1" and a.name=b.n; +-------+ | n | +-------+ | name1 | +-------+ 1 row in set (0.00 sec)别名放在表后面
select name as name1 from table1 where name1='aaa'没有办法,只能用原来的列名。select name as name1 from table1 where name='aaa'
字段别名不能直接在谓词部分引用 你的这个查询可以改成这样:select name as name1 from table1 having (name1='aaa');
a.name=b.n;
+-------+
| n |
+-------+
| name1 |
+-------+
1 row in set (0.00 sec)别名放在表后面
你的这个查询可以改成这样:select name as name1 from table1 having (name1='aaa');