title: how to find records that violate referential integrity
body: <p>I have two tables that should be in a one-to-many relationship but there seems to be some records on the many side of the table that are preventing the relationship from being created. Violates referential integrity.</p>
  
  <p>Since there are lots of records in both tables is there a way to query to see which records are in the many side, but not in the one side?</p>
  
  <pre><code>**Ex.**
  
  Table 1: (one side)
  (pk)AccountId
  
  
  Table 2: (many side)
  (pk)UserId
  (fk)AccountId  &lt;--  Some accountId's are not in Table 1 
  </code></pre>