This assumption got me in trouble as a junior analyst years ago. I was asked to analyze our customer base and wrote something like the below. Management congrat

This assumption got me in trouble as a junior analyst years ago. I was asked to analyze our customer base and wrote something like the below. Management congratulated me on finding thousands more customers than we'd ever had before. SELECT zipcode.rural_urban_code, COUNT(*) AS n_customer FROM customer INNER JOIN zipcode USING(zipcode) GROUP BY 1;