title: Exclude data based on cell value
body: <p>I am trying to exclude specific items from my pymysql query:</p>
  
  <pre><code>results = """SELECT t.id, s.name
               FROM database.table as t
               LEFT JOIN (database.secondtable as s)
               ON (t.id = s.person_id)
               WHERE s.name != 'John';"""
  db_conn pymysql.connect(host='xx', user='xx')
  df = pd.read_sql(data, con=db_conn)
  </code></pre>
  
  <p>The sql code works within my mysql serve to exclude any people who have the name John, but when I run it as the above in Python then people with the name John aren't excluded. How do I correct this within Python?</p>