title: can't set auto_increment mysql
body: <p>I have a table AAA with two columns: primary key autoincremented ID (int) and a DESCRIPTION (varchar):</p>
  
  <pre><code>ID    DESCRIPTION
  1     a description
  2     a description
  3     a description
  </code></pre>
  
  <p>I removed the last entry (ID = 3), and as supposed, when I inserted a new entry the ID was 4.</p>
  
  <pre><code>ID    DESCRIPTION
  1     a description
  2     a description
  4     a description 
  </code></pre>
  
  <p>Now I removed the ID 4, tryed to set the AUTO_INCREMENT to 3</p>
  
  <pre><code>ID    DESCRIPTION
  1     a description
  2     a description
  </code></pre>
  
  <p><i>"ALTER TABLE AAA AUTO_INCREMENT = 3"</i></p>
  
  <p>the query said ok but the AUTO_INCREMENT still remain 5. I'm using InnoDB. If there are other thing I missed let me know.</p>
  
  <p>What I have to do to set that auto increment to the very next number 3?</p>