title: pattern matching for a string of specific length in sql
body: <p>I need to query for rows from a table where one of columns matches a string whose defining characteristic is an alphanumeric string of specific length (say 4) followed by a ":" followed by an integer.</p>
  
  <ul>
  <li>pattern : alphanumericstring : integer</li>
  <li>example1: 1234:someint</li>
  <li>example2: abcd:someotherint</li>
  </ul>
  
  <p>I tried the following</p>
  
  <pre><code>select * from mytable where col1 like '[]{4}:%' 
  
  select * from mytable where col1 like '.{4}:%'
  </code></pre>
  
  <p>and neither of these work. I am aware I didn't even try to ensure that the piece following the ":" was an integer.</p>