1248

Every derived table must have its own alias

每个衍生出来的表必须要有它自己的别名。

命名一个衍生表的别名，使用AS语句。

而AS关键字的位置很多，在此情况下，放到衍生表后。

错误示范01：

执行语句：

DELETE FROM hetc_recordinfo WHERE identifier <= 40 AND votime='2017-12-14' AND sole NOT IN (SELECT * FROM (SELECT sole FROM AS list `hetc_recordinfo` WHERE identifier <= 40 AND votime='2017-12-14' GROUP BY phone) )；

执行结果：

[Err] 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'AS list `hetc_recordinfo` WHERE identifier <= 40 AND votime='2017-12-14' GROUP B' at line 1

错误示范02：

执行语句：

DELETE FROM hetc_recordinfo WHERE identifier <= 40 AND votime='2017-12-14' AND sole NOT IN (SELECT * FROM (SELECT sole FROM `hetc_recordinfo` WHERE identifier <= 40 AND votime='2017-12-14' GROUP BY phone AS list) )；

执行结果：

[Err] 1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'AS list) )' at line 1

正确示范：

执行语句：

DELETE FROM hetc_recordinfo WHERE identifier <= 40 AND votime='2017-12-14' AND sole NOT IN (SELECT * FROM (SELECT sole FROM `hetc_recordinfo` WHERE identifier <= 40 AND votime='2017-12-14' GROUP BY phone) AS list)；

执行结果：

受影响的行: 12
时间: 11.643s

（以上是删除同一表重复数据的操作）