mysql delete 多表连接删除功能

单个表的删除：

DELETE FROM tableName WHERE columnName = value;删除表内的所有行：即：保留表的结构、属性、索引DELETE FROM tablename;DELETE * FROM tablename;

TRUNCATE customer;

多表连接删除：

DELETE orders,itrms FROM orders,items   WHERE orders.userid = items.userid  AND orders.orderid = items.orderid  AND orders.date<"2000/03/01";

假设删除BV地区的所有葡萄酒场，但不删除地名

DELETE winery FROM region,winery   WHERE winery.regionid = region.regionid  AND region.regionname = 'BV';

使用高级连接查询

DELETE orders,items FROM orders  INNER JOIN otems ON orders.orderid = items.orderid  AND orders.userid = items.userid  WHERE orders.date<"2000/03/01";

也可在单一表查询中使用ORDER BY，单数除非与LIMIT连用删除部分数据行，否则并无太大意义。

加quick修饰符，可快速删除索引项，加速大量或者频繁的删除操作

DELETE QUICK FROM customer WHERE userid<10;

清理MyISAM的表

OPTIMIZE TABLE customer;

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