Question

In my table I have a field “firstname” and a field “lastname”. I would like to select all records where firstname + space + lastname is a certain value.

I’ve tried this:

$sql = "SELECT * FROM sam_users WHERE (user_firstname + ' ' + user_lastname LIKE ?)";

But this isn’t working. With Google I’ve found something about using ||, but I don’t really understand how I should use that operator. Note that I don’t want to use an or-operator (what || is in many languages), but something to concatenate 2 fields (with a space between them) and using a LIKE on that.

Thanks!

Answer 1

With MySQL, you can use CONCAT:

SELECT * FROM sam_users 
  WHERE CONCAT(user_firstname, ' ', user_lastname) LIKE ?

or CONCAT_WS (which ignores NULL values):

SELECT * FROM sam_users 
  WHERE CONCAT_WS(' ', user_firstname, user_lastname) LIKE ?

However, MySQL won’t be able to use any indices when performing this query. If the value of the pattern argument to LIKE begins with a wildcard, MySQL won’t be able to use indices, so comparing to a generated value (instead of a column) won’t make a difference.

You can also set the MySQL server SQL mode to “ANSI” or “PIPES_AS_CONCAT” to use the || operator for string concatenation.

SET @@sql_mode=CONCAT_WS(',', @@sql_mode, 'PIPES_AS_CONCAT');
SELECT * FROM sam_users 
  WHERE (user_firstname || ' ' || user_lastname) LIKE ?

This sets the SQL mode for the current session only. You’ll need to set @@sql_mode each time you connect. If you wish to unset ‘PIPES_AS_CONCAT’ mode in a session:

SET @@sql_mode=REPLACE(@@sql_mode, 'PIPES_AS_CONCAT', '');

MySQL appears to remove any extra commas in @@sql_mode, so you don’t need to worry about them.

Don’t use SELECT *; select only the columns you need.