SQL & Relational Investigation
Multi-table joins, CTEs, window functions, and row-count validation.
Overview
Structured Query Language (SQL) is the foundation of data extraction and transformation. This skill covers writing resilient queries with SELECT, WHERE, GROUP BY, HAVING, CASE, NULL handling, multi-table joins, subqueries, CTEs, and PostgreSQL window functions for cohort-level business analysis.
Why Learn This in 2026?
SQL is the universal query standard across transactional databases and modern cloud warehouses (PostgreSQL, Snowflake, BigQuery). It enables analysts to answer complex questions directly at the database layer with verifiable row counts.
How We Teach This
Week 3–4 / SQL essentials
Week 5 / SQL for deeper analysis
Explore Communities
Market Trajectory
SQL remains the single most tested skill in technical data analyst and analytics engineering interviews.
- Tested in virtually 100% of technical screening interviews for data analysts.
Hiring Landscape
Ready to master SQL & Relational Investigation?
Join our builder fellowship to master this skill through guided practice and real portfolio deliverables.
Apply Now