Programación
MVCC: How Postgres and MySQL Read Without Blocking Writes
MVCC is the mechanism that lets a SELECT query never wait for an UPDATE in progress: PostgreSQL, MySQL, and even SQLite use it to separate readers from writers. This guide explains how it works under the hood, with code examples, SQL isolation levels, and the most common mistakes when working with concurrent transactions.
Programación
Two-Phase Commit: How a Distributed Transaction Gets Coordinated
Two-phase commit is the protocol distributed databases use to confirm a transaction across multiple nodes at once, without leaving data half-written. This guide shows how to implement it with PostgreSQL, its known failure modes, and when it makes sense to replace it with Sagas or distributed consensus.









