Mysql: Table 'name' is specified twice, both as a target for 'UPDATE' and as a separate source for data
mysql在执行删除、更新的时候,可能会出现这样的错误,比如你写了类似下面的sql:
UPDATE MYTABLE SET COL=COL+1 WHERE ID IN (SELECT ID FROM MYTABLE WHERE OTHERCOL=0)
or
DELETE FROM MYTABLE WHERE ID IN (SELECT ID FROM MYTABLE WHERE OTHERCOL=0)
这个时候就会出现Table 'xxx' is specified twice这样的错误,不知道mysql为什么会做这样的冻结,知道的大神请给个链接。
要解决这个问题很简单,既然table 'xxx'不能放到子查询里面,那就做一个缓存表呗。
DELETE FROM MYTABLE WHERE ID IN (SELECT * FROM (SELECT ID FROM MYTABLE WHERE OTHERCOL=0) AS TEMP)
这样就没有问题了。