Mysql之正则匹配

Posted 2020-10-23 翎野

Regex与Like的关系
mysql中我们经常会用到正则表达式就是Like filed like ‘%?%‘ 。但是有时对于一些复杂场景下的正则过滤，单单一个like就显得有些力不从心了

Regex的精华就是 ‘‘ , like ‘%%‘ = regex ‘‘，特殊字符如^、$可以改变%的意思。

• like ‘%304%‘ = regex ‘304‘
• like ‘张%‘ = regex ‘^张‘
• like ‘%03‘ = regex ‘03$‘
• like ‘%3%‘ or like ‘%4%‘ = regex ‘[34]‘ 一个字段包含3或者包含4
• like ‘%3%‘ or like ‘%4%‘ = regex ‘3|4‘ 一个字段包含3或者包含4　

# 示例SQL---
# ‘‘ 匹配fw_ver字段中包含‘304‘字符串的所有数据：
select * from tbl_upgrade_policy where fw_ver like ‘%304%‘;
select * from tbl_upgrade_policy where fw_ver REGEXP ‘304‘;

# ^ 匹配输入字符串的开始位置
# 查找operator字段已‘张‘开头的记录
select * from tbl_upgrade_policy where operator like ‘张%‘;
select * from tbl_upgrade_policy where operator regexp ‘^李‘;

# $ 匹配输入字符串的结束位置
# 查找operator字段已‘03‘结尾的记录
select * from tbl_upgrade_policy where operator like ‘%03‘;
select * from tbl_upgrade_policy where operator regexp ‘03$‘;

# [...] 字符集合，匹配所包含的任意一个字符。
# 查询出update_type字段下为3或4或5中的任意数字
select * from tbl_upgrade_policy where update_type like ‘%3%‘ or update_type like ‘%4%‘ or update_type like ‘%5%‘;
select * from tbl_upgrade_policy where update_type REGEXP ‘[345]‘;

# p1|p2|p3 匹配 p1 或 p2 或 p3。
select * from tbl_upgrade_policy where update_type like ‘%3%‘ or update_type like ‘%4%‘;
select * from tbl_upgrade_policy where update_type REGEXP ‘3|4‘;

select * from tbl_upgrade_policy where update_type like ‘3%‘ or update_type like ‘%5‘;

# 注意：‘^[3,5]‘ 匹配以 3或,或5开头的记录
select * from tbl_upgrade_policy where update_type REGEXP ‘^[3,5]|4$‘;

# ‘^3,5‘ 匹配以 3,5 开头的记录
select * from tbl_upgrade_policy where update_type REGEXP ‘^3,5|2$‘;