# Two-Phase Locking

A protocol where a transaction acquires locks before entering a phase that only releases them.

## What is **Two-Phase Locking** in a relational database?

**Two-Phase Locking** — A protocol where a transaction acquires locks before entering a phase that only releases them.

Level: Master · [More Database terms at this level](https://www.ask-codey.com/glossary/subjects/database/master)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/two-phase-locking