Course overview

SQL & PostgreSQL Mastery

0 / 24 done0%

1. SQL Foundations

2. Aggregation & Grouping

COUNT, SUM, AVG & the NULL rule
GROUP BY: one row per group
HAVING vs WHERE
CASE & conditional aggregation

3. Joins

Keys, relationships & how joins work
INNER JOIN & multi-table queries
LEFT, RIGHT & FULL — and the filter trap
Self, cross, semi & anti-joins

4. Subqueries & CTEs

Scalar, IN & correlated subqueries
CTEs: queries as readable pipelines
Recursive CTEs for hierarchies
UNION, INTERSECT & EXCEPT

5. Window Functions

OVER & PARTITION BY
ROW_NUMBER, RANK & top-N-per-group
Frames, running totals & LAG/LEAD
SQL interview patterns

6. Performance & PostgreSQL in Practice

Indexes & the B-tree
Reading EXPLAIN plans
Schema design & constraints
Transactions, upserts & JSONB

0% complete

SQL & PostgreSQL Mastery

SQL interview patterns

This lesson is part of the full course

Enroll in SQL & PostgreSQL Mastery for lifetime access to every lesson, diagram and code template.

Enroll — ₹299 Read a free preview lesson instead

Lifetime access Instant

Previous Next lesson