title: MySQL week calculation between two dates
body: <p>I've been stuck with this issue for days, which is something like calculating the numbers of weeks that lies between two days, for example:</p>
  
  <pre><code>Select @Days = (datediff( week, @pdtFromDate, @pdtToDate) - 1) * 5
  </code></pre>
  
  <p>This returns the output as 257.</p>
  
  <p>I need to convert this script into MySQL.</p>