title: Syntax for MySQL REGEXP CONCAT
body: <p>I'm ultimately trying to make a PDO prepared statement using the REGEXP CONCAT function.  In phpmyadmin I can run the following query which returns proper results for my database contents (the 'city' value (Denver, in this case)) will eventually be the bound parameter, but I'm putting it in there explicitly now for development):</p>
  
  <pre><code>SELECT `user_ID` as `ID` 
  FROM `usermeta` 
  WHERE (`meta_key` = 'custom_field')
  AND (`meta_value` REGEXP '.*"leagues";.*s:[0-9]+:"A".*')
  AND (`meta_value` REGEXP '.*"city";.*s:[0-9]+:"Denver".*')
  </code></pre>
  
  <p>However, if I try to use the CONCAT function on the last line, the result is an empty set.  In other words, MySQL isn't throwing any errors on the query itself, but the correct data isn't being selected:</p>
  
  <pre><code>SELECT `user_ID` as `ID` 
  FROM `usermeta` 
  WHERE (`meta_key` = 'custom_field')
  AND (`meta_value` REGEXP '.*"leagues";.*s:[0-9]+:"A".*')
  AND (`meta_value` REGEXP CONCAT('\'.*"city";.*s:[0-9]+:"', 'Denver', '".*\''))
  </code></pre>
  
  <p>I've tried escaping the colon, semicolon and period characters with no luck.  Any help is very much appreciated.</p>