PostgreSQL: Foreign Key Batching Removed and Repack Fix
Postgres developers removed batched foreign-key validation to restore strict per-row correctness, and fixed concurrent repack to clear dropped-column data. There is no shared feature theme — both changes prioritize reliability over optimization.
Duration: PT2M5S
Episode overview
This episode is a short developer briefing from PostgreSQL.
It explains recent repository work in plain language.
- Show: PostgreSQL
- Published: 2026-10-03T13:03:55Z
- Audio duration: PT2M5S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Good morning, this is your PostgreSQL briefing for October 3rd, 2026.
The takeaway today is correctness over optimization. There is no single feature push, just two unrelated reliability fixes, led by a rollback of batched foreign key checks.
The highest-impact change is in commit 425daf5, which removes batching from fast-path referential integrity checks. The fast path itself stays — foreign key rows are still validated with a direct primary key index lookup instead of the heavier procedural path. What goes away is the buffering layer that delayed…
The reason matters for application developers. Delaying a foreign key check changes what it sees if another after-row trigger modifies the referenced table in between. Maintainer Amit Langote notes individual cases could be patched, but new variants kept appearing, eroding confidence that fixes would hold. Removing…
The second fix tightens concurrent repack, in commit e5d2595. During a concurrent repack, edge cases could copy a full old row into the new transient table — for example, when a trigger returns the old version during a concurrent update. That defeats the purpose of repacking, which is to shed wasted space. The fix…
What is…
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