MySQL正则表达式初步 我们知道,在SQL之中,可以用 like 这个谓词(表达式) 来进行模糊检索,并支持 %,?,_等占位符. 但是,这个模糊检索的功能有很多限制,简单来说就是太模糊了。 在MySQL中提供了 REGEXP 关键字来支持正则表达式,当然,只是一些很简单的正则啦。 首
MySQL正则表达式初步我们知道,在SQL之中,可以用 like 这个谓词(表达式) 来进行模糊检索,并支持 %,?,_等占位符.
但是,这个模糊检索的功能有很多限制,简单来说就是太模糊了。
在MySQL中提供了 REGEXP 关键字来支持正则表达式,当然,只是一些很简单的正则啦。
首先,我们构造一些测试数据。
-- 建表 USE test; DROP TABLE IF EXISTS t_regcustomer; CREATE TABLE t_regcustomer ( id INT(10) AUTO_INCREMENT ,name VARCHAR(256) ,age INT(10) , PRIMARY KEY(id) ) COLLATE='utf8_general_ci' ENGINE=InnoDB;增加一些测试数据:
-- 插入一些测试数据: TRUNCATE TABLE t_regcustomer; INSERT INTO t_regcustomer(name, age) VALUES ('王明',20); INSERT INTO t_regcustomer(name, age) VALUES ('王大',21); INSERT INTO t_regcustomer(name, age) VALUES ('小王',22); INSERT INTO t_regcustomer(name, age) VALUES ('小王2',22); INSERT INTO t_regcustomer(name, age) VALUES ('敲不死',23); INSERT INTO t_regcustomer(name, age) VALUES ('憨憨',24); INSERT INTO t_regcustomer(name, age) VALUES ('憨憨2',24); INSERT INTO t_regcustomer(name, age) VALUES ('郭靖名',25); INSERT INTO t_regcustomer(name, age) VALUES ('郭靖2',25); INSERT INTO t_regcustomer(name, age) VALUES ('郭靖3',25); INSERT INTO t_regcustomer(name, age) VALUES ('郭得缸',25) ,('大鹏',20) ,('大鹏2',20) ,('大鹏3',20) ,('二鹏',19) ,('鹏鹏',18) ,('鹏鹏1',18) ,('小鹏',17) ,('AAA',17) ,('aaa',17) ,('SS',17) ,('s2',17) ,('ss',17) ;
1. 最简单的查询:
SELECT * FROM t_regcustomer;2. 指定列名查询
SELECT c.id, c.name, c.age FROM t_regcustomer c ;3. 对查询结果排序
SELECT c.id, c.name, c.age FROM t_regcustomer c ORDER BY c.age ASC ;4. like 模糊检索
%匹配任意数量(0~n)的任意字符
SELECT c.id, c.name, c.age FROM t_regcustomer c WHERE c.name LIKE '%鹏%' ORDER BY c.age ASC ;5. regexp 关键字
.匹配任意一个字符
注意此处因为没有起始(^)和结束($)限定符,所以只要列中出现的行都会被检索出来.
SELECT c.id, c.name, c.age FROM t_regcustomer c WHERE c.name REGEXP '.鹏.' ORDER BY c.age ASC ;6. 正则起始限定符
SELECT c.id, c.name, c.age FROM t_regcustomer c WHERE c.name REGEXP '^王' ORDER BY c.age ASC ;7. 大小写敏感
SELECT c.id, c.name, c.age FROM t_regcustomer c WHERE c.name REGEXP BINARY '^s' ORDER BY c.age ASC ;8. 正则或运算
SELECT c.id, c.name, c.age FROM t_regcustomer c WHERE c.name REGEXP BINARY 'a|s' ORDER BY c.name ASC ;9. 组运算正则
[123] 表示 1、2、3这3个数字之一出现即可
SELECT c.id, c.name, c.age FROM t_regcustomer c WHERE c.name REGEXP BINARY '鹏[123]' ORDER BY c.name ASC ;[1-9] 匹配 1、2、3、.... 8、9
SELECT c.id, c.name, c.age FROM t_regcustomer c WHERE c.name REGEXP BINARY '鹏[1-9]' ORDER BY c.name ASC ;10. 转义
使用 \\
可以转义 \.[]()?-| 以及分页,换行符号等
11.更多内容
请查阅 《MySQL必知必会》 68页 正则表达式

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