title: Why does Left outer Join not use the index correctly
body: <p>I have two tables called profiles and details. The details table has index on the column city. Here is my query:</p>
  
  <pre><code>select * 
  from profiles p 
  left outer join details d 
  use index(details_city) 
   on (p.id = d.pid) 
  where (d.city = ‘york’ or p.city = 'york') 
  order by p.id
  </code></pre>
  
  <p>When I do the explain on it, I can see that index from details table on city column is not even being used. </p>
  
  <p>Is there any restriction in MySQL that it does not use indexes in such cases. </p>