title: Dataframe to_sql waiting for a long time when a table is already present
body: <p>I am using the code below to recreate the table and load data. When there is no data , the code runs successfully and the table gets created with data. When I run it the second time , the code keeps waiting for executing this line. I am ending up forcefully exiting after waiting for 10-15 minutes. I am assuming it is unable to drop the table. What could be causing this behavior?</p>
  
  <pre><code>df = pd.read_sql(query, connection)
  df_to_write.to_sql(TABLE, con=self.data_store.engine, schema=SCHEMA, if_exists='replace', index=True)
  </code></pre>