title: SQL Query - Check for Two Distinct Values
body: <p>Given the below data set I want to run a query to highlight any 'pairs' that do not consist of a 'left' and 'right'.</p>
  <pre><code>+---------+-----------+---------------+----------------------+
  | Pair_Id | Pair_Name | Individual_Id | Individual_Direction |
  +---------+-----------+---------------+----------------------+
  |       1 | A         | A1            | Left                 |
  |       1 | A         | A2            | Right                |
  |       2 | B         | B1            | Right                |
  |       2 | B         | B2            | Left                 |
  |       3 | C         | C1            | Left                 |
  |       3 | C         | C2            | Left                 |
  |       4 | D         | D1            | Right                |
  |       4 | D         | D2            | Left                 |
  |       5 | E         | E1            | Left                 |
  |       5 | E         | E2            | Right                |
  +---------+-----------+---------------+----------------------+
  </code></pre>
  <p>In this instance Pair 3 'C' has two lefts. Therefore, I would look to display the following:</p>
  <pre><code>+---------+-----------+---------------+----------------------+
  | Pair_Id | Pair_Name | Individual_Id | Individual_Direction |
  +---------+-----------+---------------+----------------------+
  |       3 | C         |  C1           | Left                 |
  |       3 | C         |  C2           | Left                 |
  +---------+-----------+---------------+----------------------+
  </code></pre>