MySQL 正则替换数据：REGEXP_REPLACE函数

用法: (此函数为MYSQL8.0版本新增，低于8.0版本没有此函数)

 REGEXP_REPLACE()函数用于模式匹配。它通过匹配字符来替换给定的字符串字符。

REGEXP_REPLACE(expr, pat, repl[, pos[, occurrence[, match_type]]])

Replaces occurrences in the string expr that match the regular expression specified by the pattern pat with the replacement string repl, and returns the resulting string. If expr, pat, or repl is NULL, the return value is NULL.

（将字符串表达式中与模式pat指定的正则表达式匹配的匹配项替换为替换字符串repl，并返回结果字符串。如果expr、pat或repl为NULL，则返回值为NULL）

REGEXP_REPLACE() takes these optional arguments:

• pos: The position in expr at which to start the search. If omitted, the default is 1.

• occurrence: Which occurrence of a match to replace. If omitted, the default is 0 (which means “replace all occurrences”).

• match_type: A string that specifies how to perform matching. The meaning is as described for REGEXP_LIKE().

Prior to MySQL 8.0.17, the result returned by this function used the UTF-16 character set; in MySQL 8.0.17 and later, the character set and collation of the expression searched for matches is used. (Bug #94203, Bug #29308212)

使用示例：

表数据

功能需求：把 name 字段中的a标签内容替换为空

实现SQL:

UPDATE tableName set `name` = REGEXP_REPLACE(`name`, '<.*>', '') WHERE `name` REGEXP '<.*>';