将PCRE正则表达式转换为mysql查询正则表达式

Question

I have below regular expression

^(?!\d+$)(?!(?:[^$&%@]*[$&%@]){4})(?!.*\b\w{11}).{3,}$

it is working fine in PHP

I want that converted to MySQL supported query. when I run above regular expression. I got error 'repetition-operator operand invalid' from reg-exp

please help to solve this

Answer 1

MySQL does not support lookarounds, nor does it support \\d or \\w classes. You may split the regex like that:

SELECT * FROM table WHERE col REGEXP '^.{3,}$' AND col NOT REGEXP '^[0-9]+$' AND col NOT REGEXP '([^$&%@]*[$&%@]){4}' AND col NOT REGEXP '[[:<:]][[:alnum:]_]{11}'

Where:

• REGEXP '^.{3,}$' - the total length should be 3 or more characters
• AND col NOT REGEXP '^[0-9]+$' - string cannot consist of digits only
• AND col NOT REGEXP '([^$&%@]*[$&%@]){4}' - string cannot have 4 special chars
• AND col NOT REGEXP '[[:alnum:]_]{11}' - string cannot have a word with 11 chars

Answer 2

The work around is to use preg-like MySQL UDF Library that has more complex REGEXP than the native MySQL's own.

https://github.com/mysqludf/lib_mysqludf_preg

and you can type the above in the link below to get Perl version of the expression that will work directly with the udf

https://regex101.com/r/wU8uM7/22/codegen?language=javascript