title: Case when using IN clause
body: <p>I need a query to return a certain result for a certain column depending on what value the column that is being run the select statement against has.</p>
  <blockquote>
  <p>if the column is one of the following : I, D, U then I want to return Y</p>
  <p>if the column is one of the following : N, E, D then I want to return N</p>
  <pre><code>                      else : I want to return NULL
  </code></pre>
  </blockquote>
  <p>I wrote the following statement but it doesn't work.</p>
  <pre><code>   SELECT HIERARCHY_TYPE,
            NODE_ID,
            NODE_TYPE,
            NODE_NAME,
            NODE_LEVEL,
            PREFERRED_ALIAS,
            PARENT_NODE_ID,
            CASE ACTIVE_INDICATOR 
               WHEN ('I' or 'U' or 'Y') THEN 'Y'
               WHEN ('D' or 'E' or 'N') THEN 'N'
               ELSE NULL
            END
       FROM MV_HIERARCHY MV;
  </code></pre>
  <p>Is there a way to rewrite it without using multiple OR clauses for each possible value?</p>