Transaction Log

Definitions

1. An append-only, sequential record of every write operation performed on a database, written to disk before the actual data pages are modified (write-ahead logging) — enabling crash recovery, replication, and point-in-time restores by replaying or undoing logged operations.

   In plain English: A running record of every change made to a database, used to recover data if something goes wrong.

   Example: "The server crashed mid-commit but the transaction log let Postgres replay the WAL and recover without data loss."

Related Terms

• WAL
• normalization
• connection pool
• graph database
• WAL Replay
• Isolation Level
• Partition Key
• Row-Level Security