title: mysql left outer join with two conditions
body: <p>I have two tables, one with user info and one with oauth info.</p>
  
  <p>I'm allowing people to have multiple oauth logins per user account - so I have an oauth table that has:</p>
  
  <p><code>ID|Provider|Identifier|UserID</code></p>
  
  <p>I can't figure out the query I would need, but I need to use this table to then find all of the user data I have with that UserID.</p>
  
  <p>So If I know the provider and identifier info, I can then use the UserID on that row, to join on the rest of the data and log the user in. Do I need a left join or something similar?</p>