title: Hash of two columns in mysql
body: <p>I have a MYSQL table, with 5 columns in it:</p>
  
  <pre><code>id bigint
  name varchar
  description varchar
  slug
  </code></pre>
  
  <p>Can I get MySQL to automatically generate the value of slug as a 256 Bit Hash of name+description?</p>
  
  <p>I am now using PHP to generate an SHA256 value of the slug prior to saving it.</p>
  
  <h1>Edit:</h1>
  
  <p>By automatic, I mean see if it's possible to change the default value of the slug field, to be a computed field that's the sha256 of name+description.</p>
  
  <p>I already know how to create it as part of an insert operation.</p>