title: Mysql query to sum decimal numbers
body: <p>I am trying to sum my decimal records e.g.</p>
  
  <p>There is a column in my table named cash having values like 40.33, 30.00, 77.22. How can I create a query that sum up these records? I am trying hard using <code>SUM(cash)</code> and <code>ROUND(SUM(cash),2)</code> but no result.</p>
  
  <pre><code>SELECT cash FROM `enrolled 
  </code></pre>
  
  <p>return rows.</p>
  
  <pre><code>SELECT ROUND(SUM(cash),2)`
  </code></pre>
  
  <p>return 0 row.</p>