SQL: The Language Every Data Professional Needs
SQL is the standard language for relational databases — used to store, retrieve, and transform data in PostgreSQL, MySQL, SQLite, and virtually every production data system. Whether you are building backend APIs, running analytics, or designing database schemas, SQL is a non-negotiable skill. This track covers the full spectrum, from your first SELECT statement through PostgreSQL-specific features like JSONB, window functions, PostGIS, and horizontal sharding.
What You Will Learn
You will start with the fundamentals: creating tables, filtering rows with WHERE, sorting with ORDER BY, and aggregating with GROUP BY. From there you will work through multi-table JOIN patterns, subqueries, CTEs, and correlated subqueries using EXISTS, ANY, and ALL. Advanced topics include window functions, recursive queries with WITH RECURSIVE, GROUPING SETS, ROLLUP and CUBE, PostgreSQL arrays and JSONB, triggers, stored procedures, row-level security, and geospatial queries with PostGIS. The track finishes at the DBA and architect level: schema migrations at scale, table partitioning, replication, high availability, performance tuning with VACUUM and ANALYZE, and sharding for horizontal scaling.
The Learning Path
Forty-six courses progress from A1 through C2. The first two courses introduce databases and relational concepts for complete beginners. A1 and A2 courses cover core querying — SELECT Mastery, Filtering Patterns, Aggregations and GROUP BY, Multi-Table Queries: JOIN Basics, and working with dates, strings, nulls, and conditional logic. B1 courses step up to Window Functions Deep Dive, Subqueries and CTEs, Recursive Queries with WITH RECURSIVE, and PostgreSQL JSON and JSONB. B2 tackles performance and production concerns: Query Performance: EXPLAIN and Planning, Index Strategies, Transactions and Concurrency Control, and Row-Level Security & Access Control. The C1 and C2 courses close with Schema Migrations at Scale, Partitioning Large Tables, Geospatial SQL with PostGIS, Event Sourcing & Temporal Tables, and Sharding and Horizontal Scaling.
How It Works
Each course is split into short, hands-on lessons you complete in the built-in SQL editor with real-time feedback on your queries. An AI tutor is available whenever you get stuck, explaining why a query returns unexpected results or how an index actually changes the execution plan.
