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Beginner to AdvancedSQLPostgreSQLDatabases

SQL & PostgreSQL Mastery

Query like an engineer — joins, indexing, window functions, and query optimization, all visual.

4.9 6 sections 24 lessons ~3h read
SQL & PostgreSQL Mastery
₹299₹199985% off
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  • Interview-focused, visual-first

What you'll learn

The relational model and the complete single-table query — SELECT, WHERE, ORDER BY, and correct NULL handling
Aggregation and grouping: GROUP BY, HAVING vs WHERE, and conditional aggregation to pivot data
Every join with visual models — INNER, LEFT/RIGHT/FULL, self, cross, and semi/anti-joins
Subqueries, CTEs, and recursive CTEs for hierarchies — turning nested queries into readable pipelines
Window functions end to end: ranking, top-N-per-group, running totals, moving averages, and LAG/LEAD
Production PostgreSQL: indexing, reading EXPLAIN plans, schema design & constraints, transactions, upserts, and JSONB

About this course

Become genuinely fluent in SQL and PostgreSQL. Start with the relational mindset and the full single-table query, then master aggregation, every kind of join, subqueries and CTEs, and the window functions that separate intermediate from advanced. Finish with the production skills — indexing, reading EXPLAIN plans, sound schema design, and Postgres-specific features like transactions, upserts, and JSONB. Every concept is taught with a running e-commerce schema, diagrams, and the exact gotchas (NULLs, WHERE vs HAVING, the LEFT JOIN filter trap) that trip people up. Interview-focused throughout.

Curriculum

6 sections · 24 lessons · ~3h

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