mysql delete limit 使用方法详解

mysql delete limit优点:

用于DELETE的MySQL唯一的LIMIT row_count选项用于告知服务器在控制命令被返回到客户端前被删除的行的最大值。本选项用于确保一个DELETE语句不会占用过多的时间。您可以只重复DELETE语句,直到相关行的数目少于LIMIT值为止。

如果DELETE语句包括一个ORDER BY子句,则各行按照子句中指定的顺序进行删除。此子句只在与LIMIT联用是才起作用。例如,以下子句用于查找与WHERE子句对应的行,使用timestamp_column进行分类,并删除第一(最旧的)行:

DELETE FROM somelog WHERE user = 'jcole' ORDER BY timestamp_column LIMIT 1;

delete limit使用方法:

单表语法:delete [low_priority] [quick] [ignore] from tbl_name

[where where_definition]

[order by ...]

[limit row_count]

删除所有行

可以在不删除表的情况下删除所有的行。这意味着表的结构、属性和索引都是完整的:

delete from table_name

或者:

delete * from table_name

下在为删除指定区别如0,30

delete from db limit 0,30

这里基本我测试都通不过,delete from db limit 30 是可以测试通过的,不知道是不是我的版本问题

好像limit 后面是指删除多少条记录,并没有给像select 中的起始记录数样!

然后如果我想limit 30 应该是删除默认的,也就跟select * from db limit 0, 30差不多,

select from `sheet1` where 1 limit 0, 1

delete from `sheet1` where 1 limit 1

对于记录数较多的情况,我们一般用limit 100

delete from tag_list where aid='6666' limit 100;

delete表连接不支持limit,该如何处理

delete表连接不支持limit

mysql> delete test1 from test1 join test2 on test1.id=test2.id limit 10;

ERROR 1064 (42000): 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 'limit 10' at line 1

mysql>

------解决思路----------------------

delete A FROM test1 A INNER JOIN (SELECT ID FROM test2 limit 10) B

on A.id=B.id ;

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