title: SELECT CASE: more than one row returned by a subquery used as an expression
body: <p>I got very good help for my question <a href="https://stackoverflow.com/questions/34771537/postgresql-return-message-after-count-0">PostgreSQL: return message after count = 0</a></p>
  
  <p>This query works fine:</p>
  
  <pre><code>SELECT  CASE WHEN COUNT(*)  = 0 THEN 'NO RESULT'
              ELSE CAST(COUNT(*) as TEXT)
          END as myfield from mytable
  </code></pre>
  
  <p>But today I need if some rows are in table, I need to show select result.</p>
  
  <p>I tried:</p>
  
  <pre><code>SELECT  CASE WHEN COUNT(*)  = 0 THEN 'NO RESULT'
               ELSE (select name from mytable)
          END as myfield from mytable
  </code></pre>
  
  <p>And I got error:</p>
  
  <blockquote>
    <p>ERROR:  more than one row returned by a subquery used as an expression</p>
  </blockquote>
  
  <p>I found that <code>IN</code> function but don't have any idea to improve it. </p>