title: Trying to perform MINUS operation in MySQL
body: <p>I am trying to perform a <code>MINUS</code> operation in MySql.I have three tables:</p>
  
  <ol>
  <li>one with service details</li>
  <li>one table with states that a service is offered in</li>
  <li>another table (based on zipcode and state) shows where this service is not offered. </li>
  </ol>
  
  <p>I am able to get the output for those two select queries separately. But I need a combined statement that gives the output as 
  'SELECT query_1  -  SELECT query_2'.</p>
  
  <p><strong>Service_Details Table</strong>
  Service_Code(PK)  Service  Name</p>
  
  <p><strong>Servicing_States Table</strong>
  Service_Code(FK)  State  Country   PK(Service_Code,State,Country)</p>
  
  <p><strong>Exception Table</strong>
  Service_Code(FK)  Zipcode  State   PK(Service_Code,Zipcode,State)</p>