概要
This skill empowers developers and data analysts to extract meaningful insights from relational databases using sophisticated SQL techniques. It provides expert guidance on crafting high-performance queries, leveraging window functions for time-series analysis, and using Common Table Expressions (CTEs) to maintain readable business logic. Whether you are calculating customer churn, performing cohort analysis, or optimizing slow-running queries, this skill ensures best practices are followed for maintainable, efficient, and accurate data workflows.
