title: Regex for start with three alpha and four digits
body: <p>I have writen an sql statement to retrieve data from Mysql db and I wanted to select data where myId start with three alpha and 4 digits example : <code>ABC1234K1D2</code></p>
  
  <pre><code>myId REGEXP '^[A-Z]{3}/d{4}' 
  </code></pre>
  
  <p>but it gives me empty result(data is available in DB). Could someone point me to correct way.</p>