title: php query(lowercase/uppercase letters) validate
body: <p>I need select result from mysql regarding query string.
  Let's string will be:
  <strong>Z</strong> and <strong>z</strong> (uppercase and lowercase)</p>
  
  <p>How database look like:</p>
  
  <pre><code>url_id      test_char
  1           Z
  2           z
  </code></pre>
  
  <p>Ok, in address bar entered: localhost/z
  This query always selecting 1 result, first one, so it returns always 1. If i try even z.</p>
  
  <p>The test_char is varchar.</p>
  
  <p>How to make Z and z select diferrent results ?</p>