title: SQL Check is there different records in table
body: <p>I want to check if there are any different records in my table. I have a <code>sales</code> table and in this table I have 2 records for same product so actually this salesman doesn't sale more than one product. I need a <code>select</code> query to check salesmen who sell more than 1 (different) product. </p>
  
  <p>Table name <code>SALES</code> -- columns <code>sales_id</code>, <code>salesman_name</code>, <code>product,name</code>, <code>quantity</code></p>
  
  <p>Need only show salesman names.</p>
  
  <p><a href="https://i.stack.imgur.com/wEhGK.png" rel="nofollow noreferrer">Example data and expectation </a></p>