title: Comparing 2 tables, and getting rows where the count is same
body: <p>Table1</p>
  
  <pre>
  ID   class
  1    A
  2    A
  3    B
  4    C
  </pre>
  
  <p>Table2</p>
  
  <pre>
  ID   class
  1    A
  3    B
  4    C
  </pre>
  
  <p>Hi, is there an easy way to compare the count(class) of each table, and if the 2 tables have the same count for that class, return the ID and class.</p>
  
  <p>Want to get the following results:</p>
  
  <pre>
  ID  class
  3   B
  4   C
  </pre>