/plushcap/analysis/cockroach-labs/why-cockroachdb-doesnt-use-evalplanqual

Why CockroachDB doesn't use EvalPlanQual

What's this blog post about?

PostgreSQL can sometimes miss rows when performing UPDATE, DELETE, SELECT FOR UPDATE, or SELECT FOR SHARE statements under READ COMMITTED isolation due to the EvalPlanQual recheck. This behavior can cause anomalies and may require application-level retries. CockroachDB's new implementation of READ COMMITTED isolation uses a different technique that does not miss rows, thus alleviating the need for application-level retries.

Company
Cockroach Labs

Date published
April 5, 2024

Author(s)
Michael Erickson

Word count
1707

Hacker News points
135

Language
English


By Matt Makai. 2021-2024.