title: PHP - Send Email, compare database current timestamp(reminder)send mail before one day and one hour to user
body: <p>I'm trying to send  autoresponder mail for all user. 
  In database field name coursedate(current timestamp) . I need to send the mail one day before the course date and one hour before cause time.</p>
  
  <p>For example </p>
  
  <blockquote>
    <p>coursedate: 2015-05-25</p>
    
    <p>I need send mail on 2015-05-24 (before 24 hours) </p>
    
    <p>and before one hour on (2015-05-25)</p>
  </blockquote>
  
  <p>How to do in php or mysql query</p>