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Write and evaluate live SQL queries directly in your browser. Practice relational JOINs, aggregations, subqueries, CTEs, and window functions against pre-populated HR, E-Commerce, and Rideshare schemas.
Master relational database concepts, SQL command pillars (DQL, DDL, DML, DCL), data types, and foundational SQL syntax.
Master SELECT, WHERE, ORDER BY, LIMIT, DISTINCT, BETWEEN, LIKE, IN, IS NULL, and basic column aliasing.
Combine multi-table datasets using INNER JOIN, LEFT/RIGHT OUTER JOINs, self-joins, and CROSS JOINs.
Aggregate datasets using COUNT, SUM, AVG, and filter consolidated data groups using HAVING.
Manipulate text, math, and dates with built-in functions, and implement conditional log mappings.
Leverage scalar, row, correlated and EXISTS nested subqueries to solve complex data comparisons.
Structure temporary query sets with WITH CTEs, and perform operations using UNION, EXCEPT, INTERSECT.
Perform relative partition operations using ROW_NUMBER, RANK, DENSE_RANK, LAG, and LEAD window frames.
Verify normal forms, map key constraints (FK, PK, UNIQUE), and enforce referential check rules.
Scenario-focused FAANG SQL Interview playbook covering JOINs, CTEs, and window functions.
Ride-sharing logistics data metrics, driver payout calculations, and dispatch queries.
Healthcare audit query patterns, patient appointment timelines, and clinical data metrics.