This article explains how to use SQL and the haversine formula to send highly personalized email drip campaigns based on user location. The author provides a step-by-step guide on how to query through lead data containing geographic coordinates to find users who Yelp within five miles of a business, have Yelped more than five times about businesses like the example business, and give at least a four-star average review. The article covers various SQL concepts such as joins, subqueries, and aggregations to achieve these goals. By operationalizing this data using reverse ETL, businesses can easily sync their data warehouse with frontline tools to fuel their email campaigns.