delete 删除 删除表中已存在的整行数据。 `delete from table_name where ...order by ...limit...` 如果没有where条件则会删除整个表。 `delete from students order by sid limit 1; `删除以sid升序排序的第一条记录。 多表删除：两种用法： ~~~ delete a1,a2 from t1 as a1 inner join t2 as a2 where a1.id=a2.id; DELETE FROM a1, a2 USING t1 AS a1 INNER JOIN t2 AS a2 WHERE a1.id=a2.id; ~~~ `delete <alias> from <table> <alias> where <alias>.<field>...` 别名必需在 delete之后出一次。