Have you ever been writing a search for MySQL and had an issue where the search wouldn’t handle spaces properly?

I was writing a search for a users table and wanted to find a user by their first name or last name or a combination of both.

I started with a query like this:

SELECT * FROM `users`
  WHERE LOWER(`users`.`first_name`)
      LIKE LOWER(:searchTerm)
    OR LOWER(`users`.`last_name`)
      LIKE LOWER(:searchTerm)

Here is the list for the matches, given that there is a user with the first_name of “James” and last_name of “Doyle”:

  • ”%james%” - match
  • ”%doyle%” - match
  • ”%james d%” - no match
  • ”%j doyle%” - no match
  • ”%james doyle%” - no match

The issue comes in when you add spaces into the search query. I didn’t want to split the word into an array and do a search for each word. That would require querying the database multiple times. And I don’t want to try to do RLIKE and all these string hacks to get this to match more accurately.

Well, I found this trick where you can create fake columns using the CONCAT and then replace any space character with %.

So if I queried like this: %james doyle%, that will actually become %james%doyle% when it gets to the actual SQL WHERE query.

This allows you to get a better match more often if the user types in more content in a query with a space.

SELECT * FROM `users`
  WHERE
    LOWER(CONCAT(`users`.`first_name`,`users`.`last_name`))
      LIKE LOWER(REPLACE(:searchTerm, " ", "%"))

Here is a list of terms that will be matched in this query:

  • ”%james%” - match
  • ”%doyle%” - match
  • ”%james d%” - match
  • ”%j doyle%” (becomes “%j%doyle%” due to REPLACE) - match
  • ”%james doyle%” (becomes “%james%doyle%” due to REPLACE) - match

Sidenote

The only downside of this query is that you may get more matches if the string you are searching for is too small. Like 2 - 3 characters. At that point though, you should notify the user that they should enter in more characters to get more accurate results.

Another great thing is that if you added a middle_name column, it will handle searches where someone is searching for a known first and middle name as well. It can still match as the CONCAT builds a nice string to match against.