Understanding Logical Decoding and Replication
summary
Explains that PostgreSQL 9.4 adds logical replication slots and a plugin API that reads WAL, decodes changes, and exposes them over the replication protocol or SQL functions; shows a working decoder that emits decoder-generated SQL and a background worker that applies changes to a second master; warns that it produces one change per tuple (bulk COPY of 1M rows yields 1M changes), requires max_replication_slots and exported snapshots handling, and demonstrates an async multimaster prototype that actually works.
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chapters (18)
- 0:00Introduction
- 3:15Where is Logical Decoding
- 4:06What is Logical Decoding
- 5:38Replication Slots
- 7:55Physical Slots
- 9:00Reputation Slots
- 10:42Logical Replication Slots
- 12:35Export Snapshots
- 17:28Output Decoding
- 19:53Replica Identity
- 24:01Replication
- 27:57Synchronous Commit
- 29:30Basic Understanding
- 34:07Hacking
- 40:10SQL Interface
- 41:31Replication Protocol
- 44:34Online Upgrade
- 50:49Receiving Changes
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