title: MySQL: How to alter varchar(255) UNIQUE column to UNIQUE Text NOT NULL?
body: <p>The current column is a VARCHAR(255) NOT NULL, so how do I change it to TEXT NOT NULL?</p>
  
  <p>NOTE: The column intended to be changed its property type is a UNIQUE KEY combination of another column. E.g.</p>
  
  <p>UNIQUE KEY (Name, Description)</p>
  
  <p>The column description is currently in varchar(255). It can't be changed because of this:</p>
  
  <blockquote>
    <p>ERROR 1170 (42000): BLOB/TEXT column 'description' used in key specification without a key length</p>
  </blockquote>
  
  <p>I need it to be TEXT, else I need to recreate the whole thing?? I got some tedious and important data already in it. It's going to be troublesome to recreate. </p>