数据库|mysql教程
关键字,表达式,mysql,where
数据库-mysql教程
如下为mysql必知必会第九章开始:
彩虹全解密源码,vscode横线怎么做,ubuntu 开机执行,tomcat项目没启动,爬虫 工具 nutch,php接口session,seo系统优化有哪些方法,手游分发网站源码,手机网站模板html源码下载lzw
正则表达式用于匹配特殊的字符集合。mysql通过where子句对正则表达式提供初步的支持。
yy电影网站源码程序,vscode一键编译c,ubuntu内核删除,tomcat短域名访问,scrapy 爬虫源码,php endfor,汕头市seo网络推广企业lzw
关键字regexp用来表示后面跟的东西作为正则表达式处理。
文件上传和下载系统源码,树莓派 虚拟 Ubuntu,狗屁股爬虫子,php剔除标签,seo_sexo少女lzw
(.)是正则表达式的一个符号,表示匹配任意一个字符:
mysql> select prod_name-> from products-> where prod_name regexp .000-> order by prod_name;+--------------+| prod_name|+--------------+| JetPack 1000 || JetPack 2000 |+--------------+2 rows in set (0.14 sec)
|匹配符:
表示匹配其中之一
mysql> select prod_name-> from products-> where prod_name REGEXP 1000|2000-> ORDER BY prod_name;+--------------+| prod_name|+--------------+| JetPack 1000 || JetPack 2000 |+--------------+2 rows in set (0.00 sec)
[]匹配符: 匹配几个字符之一
2 rows in set (0.00 sec)mysql> select prod_name-> from products-> where prod_name regexp [123] Ton-> ;+-------------+| prod_name |+-------------+| 1 ton anvil || 2 ton anvil |+-------------+2 rows in set (0.00 sec)
mysql> select prod_name from products where prod_name regexp [1-5] Ton;+--------------+| prod_name|+--------------+| .5 ton anvil || 1 ton anvil|| 2 ton anvil|+--------------+3 rows in set (0.02 sec)
mysql> select prod_name from products where prod_name regexp [^1-3] Ton;+--------------+| prod_name|+--------------+| .5 ton anvil |+--------------+1 row in set (0.00 sec)
匹配特殊字符,必须用//为前导。
mysql> select prod_name from products where prod_name regexp //. ;+--------------+| prod_name|+--------------+| .5 ton anvil |+--------------+1 row in set (0.00 sec)
匹配字符类:
mysql> select prod_name from products where prod_name REGEXP //([0-9] sticks?//) order by prod_name;+----------------+| prod_name|+----------------+| TNT (1 stick)|| TNT (5 sticks) |+----------------+2 rows in set (0.05 sec)mysql> select prod_name from products where prod_name REGEXP [[:digit:]]{4} order by prod_name;+--------------+| prod_name|+--------------+| JetPack 1000 || JetPack 2000 |+--------------+2 rows in set (0.00 sec)
定位符用法:
mysql> select prod_name-> from products-> where prod_name REGEXP ^[0-9//.]-> order by prod_name;+--------------+| prod_name|+--------------+| .5 ton anvil || 1 ton anvil|| 2 ton anvil|+--------------+3 rows in set (0.00 sec)
以上都是mysql正则表达式的用法。