title: How to select rows according to a regex?
body: <p>I have a table like this:</p>
  
  <pre><code>// mytable
  +----+----------------------+
  | id |       sentence       |
  +----+----------------------+
  | 1  | thIs! is, a** tEst?  |
  | 2  | and also This ^ is&amp;  |
  | 3  | --it^% is tOo.       |
  +----+----------------------+
  </code></pre>
  
  <p>Also I have a variable:</p>
  
  <pre><code>$str = "this-is-a-test";
  /* the above string is made according to this:
     strtolower(trim(preg_replace('~[^0-9a-z]+~i', '-', $str)));
  */
  </code></pre>
  
  <p>Also here is my query:</p>
  
  <pre><code>SELECT * FROM mytable WHERE sentence = '$str';
  </code></pre>
  
  <p>Now I want this <strong>output:</strong></p>
  
  <pre><code>+----+----------------------+
  | id |       sentence       |
  +----+----------------------+
  | 1  | thIs! is, a** tEst?  |
  +----+----------------------+
  </code></pre>
  
  <hr>
  
  <p>How can I apply that regex on column temporarily before searching?</p>