title: MySQL Query LEFT OUTER JOIN AND IFNULL
body: <p>I have this query: </p>
  
  <pre><code>SELECT st.st_id, st.id, st.name, at.status, at.date
  FROM st,at
  WHERE st.st_id = at.at_id;
  </code></pre>
  
  <p>but I want the result return all of <code>st</code> table, if <code>st</code>.st_id exist in <code>at</code>.st_id, the status column is what in the <code>at</code> table, if not the status is 'H', anyone can help?
  <a href="https://i.stack.imgur.com/3zfbF.png" rel="nofollow noreferrer">this is my table column</a></p>