title: SQL Multiple Row Subquery
body: <p>I have a table <code>Studies</code> that I perform a SELECT on.</p>
  
  <p>I then need to perform a further SELECT on the recordset returned.  I've tried this (simplified for clarity):</p>
  
  <pre><code>SELECT * FROM Studies
  WHERE Id = '2' OR Id = '3' OR Id = '7';
  </code></pre>
  
  <p></p>
  
  <pre><code>SELECT * FROM Studies
  WHERE (Name = 'Test')
    AND Id IN (SELECT * FROM Studies WHERE Id = '2' OR Id = '3' OR Id = '7');
  </code></pre>
  
  <p>But I keep getting the following SQL error:  </p>
  
  <blockquote>
    <p>Only a single result allowed for a SELECT that is part of an expression</p>
  </blockquote>
  
  <hr>
  
  <p>Where am I going wrong? If it's not evident from my code - I am relatively new to database programming.</p>
  
  <p>Thanks</p>