SQL

Apr 21, 2024 Databases 40 min read

Databases (3): Transactions and Concurrency — ACID, Isolation Levels, and Locking

A thorough guide to ACID properties, isolation levels, MVCC, locking strategies, and deadlock prevention — with concrete SQL examples for every concept.

Apr 19, 2024 Databases 36 min read

Databases (2): Indexing and Query Planning — How Databases Find Your Data

Deep dive into B-tree and B+tree indexes, hash indexes, composite indexes, covering indexes, and how to read EXPLAIN output to diagnose slow queries.

Apr 17, 2024 Databases 42 min read

Databases (1): Data Models and SQL — Why Tables Won (For Now)

A ground-up tour of the relational model, SQL fundamentals, normalization, and advanced query patterns — everything you need to speak fluent SQL.