title: Mysql Error: #1075
body: <p>SQL query:</p>
  
  <pre><code>ALTER TABLE  `blog` CHANGE  `id`  `id` BIGINT NOT NULL AUTO_INCREMENT
  </code></pre>
  
  <p>MySQL said: </p>
  
  <pre><code>#1075 - Incorrect table definition; there can be only one auto column and it must be defined as a key 
  </code></pre>
  
  <p>I am trying to create a blog, and I got the code done. Now, I need to make the <code>id</code> auto increase, but I get this error. Why am I getting this?</p>