title: mysql - can I set VARCHAR default value as NULL?
body: <p>In mysql, i tried changing an existing table like this:</p>
  
  <pre><code>  ALTER TABLE  `etexts` CHANGE  `etext`  `etext` VARCHAR( 100 ) CHARACTER SET latin1 COLLATE latin1_swedish_ci NOT NULL DEFAULT NULL
  </code></pre>
  
  <p>I got the response:</p>
  
  <pre><code>  #1067 - Invalid default value for 'etext' 
  </code></pre>
  
  <p>Why?</p>