Topic Overview

SQL

SELECT, JOINs, indexes, transactions, backups.

3 articles

SQL in 10 Minutes — Your First Queries and Core Mental Model

Complete beginner guide to SQL querying, clause execution order, SELECT, WHERE, ORDER BY, LIMIT, NULL logic, grouping, and transaction safety.

4 min read 2026-10-06

sql database select

SQL JOINs Explained with Visual Examples and Code

Master INNER JOIN, LEFT JOIN, RIGHT JOIN, and anti-joins with step-by-step beginner explanations, table diagrams, and syntax breakdowns.

4 min read 2026-10-06

sql joins inner-join

SQL Indexes and EXPLAIN — How to Optimize Database Queries

Complete beginner guide to understanding B-tree indexes, reading EXPLAIN query plans, avoiding full table scans, and knowing when indexes hurt performance.

3 min read 2026-10-06

sql indexes performance