title: Can I make a daily reward function in PHP?
body: <p>In my MySQL database, there is a column named "heart" like:</p>
  
  <pre><code>ID  NAME  HEART
  001 AAA   5
  002 BBB   22
  003 CCC   15
  004 DDD   12
  </code></pre>
  
  <p>So how can I make daily reward function that if user login everyday, they will get one more heart everyday. Is there any example about this? Many thanks.</p>