Search for "whole word match" in MySQL

Question

I would like to write an SQL query that searches for a keyword in a text field, but only if it is a "whole word match" (e.g. when I search for "rid", it should not match "arid", but it should match "a rid".

I am using MySQL.

Fortunately, performance is not critical in this application, and the database size and string size are both comfortably small, but I would prefer to do it in the SQL than in the PHP driving it.

Answer 1

You can use REGEXP and the [[:<:]] and [[:>:]] word-boundary markers:

SELECT * FROM table  WHERE keywords REGEXP '[[:<:]]rid[[:>:]]' 

Update for 2020: (actually 2018+)

MySQL updated its RegExp-Engine in version 8.0.4, so you will now need to use the "standard" word boundary marker \b:

SELECT * FROM table  WHERE keywords REGEXP '\\brid\\b' 

Also be aware that you need to escape the backslash by putting a second backslash.

Answer 2

Found an answer to prevent the classic word boundary [[::<::]] clashing with special characters eg .@#$%^&*

Replace..

SELECT * FROM table  WHERE keywords REGEXP '[[:<:]]rid[[:>:]]' 

With this..

SELECT * FROM table  WHERE keywords REGEXP '([[:blank:][:punct:]]|^)rid([[:blank:][:punct:]]|$)' 

The latter matches (space, tab, etc) || (comma, bracket etc) || start/end of line. A more 'finished' word boundary match.