title: Is there a way to give a subquery an alias in Oracle 11g SQL?
body: <p>Is there a way to give a subquery in Oracle 11g an alias like:</p>
  
  <pre><code>select * 
  from
      (select client_ref_id, request from some_table where message_type = 1) abc,
      (select client_ref_id, response  from some_table where message_type = 2) defg
  where
      abc.client_ref_id = def.client_ref_id;
  </code></pre>
  
  <p>Otherwise is there a way to join the two subqueries based on the client_ref_id.  I realize there is a self join, but on the database I am running on a self join can take up to 5 min to complete (there is some extra logic in the actual query I am running but I have determined the self join is what is causing the issue).  The individual subqueries only take a few seconds to complete by them selves.  The self join query looks something like:</p>
  
  <pre><code>select st.request, st1.request
  from
      some_table st, some_table st1
  where 
      st.client_ref_id = st1.client_ref_id;
  </code></pre>