MYSQL的模式查询
另外一种是用正则表达式匹配。 如查询所有owner为#39;陈...#39;的pet. select * from pet where owner regexp #39;^陈#39;; 或select *
假设MYSQL有一数据库,它有一个表pet.
+---------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+-------------+------+-----+---------+-------+
| name | varchar(20) | YES | | NULL | |
| owner | varchar(20) | YES | | NULL | |
| species | varchar(20) | YES | |p NULL | |
| sex | char(1) | YES | | NULL | |
| birth | date | YES | | NULL | |
| death | date | YES | | NULL | |
+---------+-------------+------+-----+---------+-------+
一种是sql的标准匹配。
查询name以b开头的所有记录:
select * from pet where name like 'b%';
这里的'%'类似于windows系统下面的'*',而'_'类似于 windows下面的'?'。
另外一种是用正则表达式匹配。
如查询所有owner为'陈...'的pet.
select * from pet where owner regexp '^陈';
或select * from pet where owner rlike '^陈';
找出pet name正好为4他字符的情况。
select * from where name rlike '^{4}$';
或select * from where name rlike '^....$';
这些和一般的正则表达式的用法是类似的。

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