SQL Beginner ~45 h 0 students enrolled

SQL

Complete SQL course: from SELECT and JOIN to window functions, query optimization and database design. Working with PostgreSQL.

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34 lessons
16 exercises
3435 XP for course
~45 h

What You'll Learn

What Are Databases?
Creating Tables
INSERT — Adding Data
SELECT — Querying Data
UPDATE & DELETE
Aggregate Functions
JOIN — Joining Tables
Subqueries
String Functions
Date & Time
CASE & Conditional Logic
Keys & Relationships
Indexes
Views
Transactions
Window Functions
UNION & Set Operations
JSONB (PostgreSQL)
Database Normalization
Query Optimization
Stored Procedures
Security
Full-Text Search
Recursive Queries
Database Design
Migrations & Tools
Project: E-Commerce
Project: Analytics
Project: SQL Cheat Sheet
What's Next?

This Course Includes

Interactive exercises with instant feedback
Real compiler in your browser
Certificate upon completion
Gamification: XP, levels, badges

Curriculum

30 lessons · 34 lessons · 16 exercises

1

What Are Databases?

Relational DB, tables, rows, columns, DBMS

  • Databases & SQL +10 XP
  • SQL Categories +10 XP
2

Creating Tables

CREATE TABLE, data types, PRIMARY KEY, NOT NULL

  • CREATE TABLE +15 XP
3

INSERT — Adding Data

INSERT INTO, VALUES, multi-insert, RETURNING

  • INSERT INTO +10 XP
4

SELECT — Querying Data

SELECT, WHERE, ORDER BY, LIMIT, DISTINCT

  • SELECT Basics +15 XP
5

UPDATE & DELETE

Updating and deleting data, TRUNCATE, safety

  • UPDATE & DELETE +15 XP
6

Aggregate Functions

COUNT, SUM, AVG, MIN, MAX, GROUP BY, HAVING

  • COUNT, SUM, AVG, MIN, MAX +15 XP
7

JOIN — Joining Tables

INNER, LEFT, RIGHT, FULL, CROSS JOIN

  • JOIN Types +15 XP
  • JOIN Practice +10 XP
8

Subqueries

Nested queries, IN, EXISTS, scalar, CTE

  • Subqueries +15 XP
9

String Functions

CONCAT, UPPER, LOWER, TRIM, SUBSTRING, LIKE, ILIKE

  • String Functions +10 XP
10

Date & Time

DATE, TIMESTAMP, INTERVAL, EXTRACT, formatting

  • Working with Dates +10 XP
11

CASE & Conditional Logic

CASE WHEN, COALESCE, NULLIF, conditional aggregates

  • CASE WHEN +15 XP
12

Keys & Relationships

PRIMARY KEY, FOREIGN KEY, 1:1, 1:N, N:N relationships

  • Primary & Foreign Keys +15 XP
13

Indexes

B-tree, CREATE INDEX, composite, partial, EXPLAIN

  • Indexes & Performance +10 XP
14

Views

CREATE VIEW, materialized views, updatable

  • Views — Virtual Tables +10 XP
15

Transactions

BEGIN, COMMIT, ROLLBACK, ACID, isolation levels

  • ACID & Transactions +10 XP
16

Window Functions

ROW_NUMBER, RANK, LAG, LEAD, OVER, PARTITION BY

  • Window Function Basics +15 XP
  • LAG, LEAD & Frames +10 XP
17

UNION & Set Operations

UNION, INTERSECT, EXCEPT, combining results

  • Set Operations +10 XP
18

JSONB (PostgreSQL)

Storing JSON, operators, GIN indexes, jsonb_agg

  • Working with JSONB +10 XP
19

Database Normalization

1NF, 2NF, 3NF, denormalization, when to break rules

  • Normal Forms +10 XP
20

Query Optimization

EXPLAIN ANALYZE, execution plans, N+1, best practices

  • EXPLAIN & Optimization +10 XP
21

Stored Procedures

Functions, procedures, PL/pgSQL, triggers

  • Functions & Triggers +10 XP
22

Security

SQL injection, GRANT, REVOKE, roles, RLS

  • SQL Security +10 XP
23

Full-Text Search

tsvector, tsquery, GIN, pg_trgm, ranking

  • Text Search in PostgreSQL +10 XP
24

Recursive Queries

Recursive CTE, hierarchies, trees, graphs

  • Recursive CTE +10 XP
25

Database Design

ER diagrams, schema design, best practices

  • Schema Design +15 XP
26

Migrations & Tools

Migrations, psql, pgAdmin, ORM, Rails migrations

  • Migrations & Tools +10 XP
27

Project: E-Commerce

Designing e-commerce database

  • E-Commerce Schema +20 XP
28

Project: Analytics

Analytics queries with window functions

  • Analytics Queries +20 XP
29

Project: SQL Cheat Sheet

HTML cheat sheet of SQL commands

  • SQL Cheat Sheet +20 XP
30

What's Next?

Career paths, final test

  • What's Next After SQL? +10 XP
  • Final Quiz +20 XP

Requirements

No prior knowledge required — we start from scratch

Course FAQ

Do I need programming experience?
Not at all! This course is built for complete beginners. We start from the basics and gradually increase complexity.
How do lessons work?
Each lesson includes theory with examples and interactive exercises. You write code right in your browser, and our compiler checks the result.
How long does the course take?
On average, you can complete the course in a few days at 1-2 hours per day. But there's no rush — learn at your own pace.
Will I get a certificate?
Yes! After completing all lessons and exercises, you'll receive an electronic certificate with a unique ID.

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