title: ERROR 1109 (42S02): Unknown table 'comment' in field list
body: <p>I work with MySQL 5.5. I have a table <code>comment</code>.
  When I make this query:</p>
  
  <pre><code> select sum(case when comment.entity_id=1 and comment.entity_type=1 then 1 else 0 end) as result1;
  </code></pre>
  
  <p>I get </p>
  
  <pre><code>ERROR 1109 (42S02): Unknown table 'comment' in field list
  </code></pre>
  
  <p>This should not happen, since </p>
  
  <pre><code>select * from comment;
  </code></pre>
  
  <p>works just fine.</p>
  
  <p>Where is the error?</p>