Databases
SQL, NoSQL, and everything in between.
01Databases (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 …
02Databases (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 …
03Databases (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 …
04Databases (4): Storage Engines — How Data Hits Disk
How database storage engines work under the hood — B-tree vs LSM-tree, WAL, buffer pools, compaction, and why your …
05Databases (5): NoSQL — Document, Key-Value, Column, and Graph
A practical tour of the four major NoSQL families — document, key-value, wide-column, and graph — including the CAP …
06Databases (6): Replication and Partitioning — Scaling Beyond One Machine
How databases replicate data for availability and partition data for scale — covering leader-follower, multi-leader, …
07Databases (7): Distributed Transactions — 2PC, Saga, and Why Consensus Is Hard
How distributed databases coordinate transactions across machines — two-phase commit, Raft consensus, the Saga pattern, …
08Databases (8): Databases in Practice — Migration, Monitoring, and War Stories
The operational side of databases — schema migrations, connection pooling, monitoring, backup strategies, managed …