title: SQL query to Rank Customers by the number of unique merchants they have used
body: <p>I am trying to Rank Customers by the number of unique merchants they have used.</p>
  
  <p>Request you to help me out with the SQL code.</p>
  
  <p>You can view the data from the below link:
  <strong><em><a href="https://www.kaggle.com/ntnu-testimon/banksim1#bs140513_032310.csv" rel="nofollow noreferrer">https://www.kaggle.com/ntnu-testimon/banksim1#bs140513_032310.csv</a></em></strong></p>