Introduces the fundamentals of relational databases, different types of data, and how to query them. Offers instruction in writing complex queries that pull, join, filter, and summarize complex data from multiple sources. Analyzes cleaning, transforming, and aggregating data, and touches on advanced topics such as window functions and complex data types. Assesses the efficiency of queries and emphasizes the importance of minimizing runtime. Demonstrates how to integrate database access with common analytical programming languages. Applies these techniques to real-world case studies similar to those offered in case interview scenarios.