今天删除数据，写了这么条sql语句，
DELETE from sys_menus s WHERE s.MENU_ID in (86,87,88);
结果报错。。
[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 's WHERE s.MENU_ID in (86,87,88)' at line 1
后来一查，mysql使用别名有固定的语法。
当然不用也行：DELETE from sys_menus WHERE MENU_ID in (86,87,88);
用别名的：DELETE s from sys_menus s WHERE s.MENU_ID in (86,87,88);
转的！原博文网址：http://blog.csdn.net/chs_jdmdr/article/details/46708917
deletefrom
别名必需在 delete之后出一次。
多表间删除语法：
DELETE t1, t2 FROM t1 INNER JOIN t2 INNER JOIN t3
WHERE t1.id=t2.id AND t2.id=t3.id;
Or:
DELETE FROM t1, t2 USING t1 INNER JOIN t2 INNER JOIN t3
WHERE t1.id=t2.id AND t2.id=t3.id;
LEFT JOIN:
DELETE t1 FROM t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t2.id IS NULL;