In my AtliQ Mart project, I focused on optimizing SQL queries to ensure efficient data retrieval and processing. I utilized JOINs to combine data from multiple tables, which allowed me to analyze sales metrics and promotional performance effectively. For instance, I joined the sales and promotions tables to assess the impact of different campaigns on sales volume. Additionally, I used Common Table Expressions (CTEs) to simplify complex queries and improve readability. By breaking down the queries into manageable parts with CTEs, I was able to perform calculations and transformations more efficiently. I also implemented indexing on frequently queried columns to speed up data access and reduce query execution time. This approach not only enhanced the performance of the queries but also provided valuable insights into sales trends and promotional effectiveness.