title: Comparing with NULL values
body: <pre><code>CREATE TABLE `mycompare` (
    `name` varchar(100) default NULL,
    `fname` varchar(100) default NULL,
    `mname` varchar(100) default NULL,
    `lname` varchar(100) default NULL
  ) ENGINE=MyISAM DEFAULT CHARSET=utf8;
  
  INSERT INTO `mycompare` VALUES('amar', 'ajay', 'shankar', NULL);
  INSERT INTO `mycompare` VALUES('akbar', 'bhai', 'aslam', 'akbar');
  INSERT INTO `mycompare` VALUES('anthony', 'john', 'Jim', 'Ken');
  _____
  
  SELECT * FROM mycompare WHERE (name = fname OR name = mname OR name = lname)
  akbar   bhai    aslam   akbar
  
  select * from mycompare where !(name = fname OR name = mname OR name = lname)
  anthony john    Jim Ken
  </code></pre>
  
  <p>In the second select above, I expect the "amar" record as well because that name does not match with First, second or last name.</p>