title: How to select the highest sum of value in mysql
body: <p>I have the table like this</p>
  
  <pre><code>id    rate_user_id   content_id     points  category_id
  1      100              1                  5      1
  2      101              1                  3      1
  3      100              2                  8      1
  4      103              2                  11     1
  </code></pre>
  
  <p>So I want to looking highest point of content in this  category 1</p>
  
  <p>Content_id 2 = 19 points .</p>