- Welcome to this section of my portfolio, here I showcase my expertise in SQL (MySQL and Google BigQuery) through various case studies. These projects demonstrate my ability to analyze and explore business questions - thereby generating actionable insights from datasets.
Feel free to connect with me via: LinkedIn Tosin Folorunso, Email: tosin.folorunso01@gmail.com
Danny is growing a Japanese restaurant, but he's missing the insights he needs to truly understand his customers. Danny is concerned about finding answers to a couple of business questions - he doesn’t have a clear view of how often his customers visit, how much they spend, or which menu items they love the most. Without this information, it’s difficult for him to build deeper relationships with his loyal customers or make confident decisions about expanding his loyalty program. Additionally, his team doesn’t have the technical skills to dig into the raw data, which means they can’t quickly answer important questions or make data-driven decisions.
- Writing CREATE TABLE and INSERT statements to build and populate databases
- Using JOINs (INNER JOIN, LEFT JOIN) to combine data from multiple tables
- Applying aggregate functions like COUNT and SUM with GROUP BY for summary data
- Writing window functions (ROW_NUMBER(), RANK()) for ranking and partitioning data
- Using CASE statements for conditional logic within queries
- Structuring subqueries and derived tables for complex data analysis