title: how to find people with the same first and last name
body: <p>so i had a table with 3 columns:
  id \ first_name \ last_name
  and i need to find how many of people share the same full name.
  i had something like this:</p>
  
  <pre><code>SELECT COUNT(*) 
  FROM ACTOR 
  WHERE FIRST_NAME IN (SELECT FIRST_NAME,LAST_NAME 
              FROM ACTOR
              HAVING COUNT(FIRST_NAME,LAST_NAME) &gt;1);
  </code></pre>