title: mysql functionality like 'show processlist' with client code info
body: <p>Executing <code>show processlist;</code> in mysql shows me what threads are running. Is there way to get information about the code that started the thread?</p>
  
  <p>Example: </p>
  
  <pre><code>+--------+------+-----------+--------+---------+-------+-------+--------+-------------------+
  | Id     | User | Host      | db     | Command | Time  | State | Info   | code_info         |
  +--------+------+-----------+--------+---------+-------+-------+--------+-------------------+
  | 123    | db   | localhost | db1    | Query   | 52    | Sen.. | SELE.. | /path/to/file.php |
  |        |      |           |        |         |       |       |        | line 1 34         |
  +--------+------+-----------+--------+---------+-------+-------+--------+-------------------+
  </code></pre>
  
  <p>My current solution is to put a comment in every single sql statement I execute like this:</p>
  
  <pre><code>   /* file: path/to/file.php class: testclass */ 
     SELECT  *
     FROM table
     WHERE id = 1;
  </code></pre>