title: How to write case logic in SQL
body: <p>I have a scenario where i want to write SQL case logic for below</p>
  <p><em>Not understanding when to make use of symbol <code>'&lt;&gt;'</code></em></p>
  <p><strong>Logic 1 :</strong></p>
  <pre><code>if [ employee_name] = 'ABC' then
  empcode='ABC'
  empcourse=Null
  </code></pre>
  <p><strong>Logic 2 :</strong></p>
  <pre><code>if [ employee_name] &lt;&gt; 'ABC' then
  empcode='PQR-N'
  empcourse='MBA'
  </code></pre>
  <p><strong>Below is the query i tried writing :</strong></p>
  <pre><code>case
      when employee_name equal ABC and empcode equal 'ABC'
      then 
      empcode='ABC'
      empcourse=Null
  </code></pre>