title: How can I optimize this SQL query (Using Indexes)?
body: <p>There is a query which runs more slowly than I would like, but I cannot share the details. The query returns the correct results already, and I have refactored it, but I cannot get it to run quickly enough. The predicates are already <a href="https://stackoverflow.com/questions/799584/what-makes-a-sql-statement-sargable">Sarg-able</a> where possible. It is already properly using joins, requests no extra tables, and does not unnecessarily replicate rows or use nested subqueries in ways that would slow it down.</p>
  
  <p>I’m not a DBA, and I don’t already know how to pick a good index to make my query faster. I can alter the table structures; there is no DBA in charge of the database, and I have the permissions on the database server to do so. </p>
  
  <p>What are the steps I should take to optimize my SQL Query?</p>