Citus 11 is out! Now 100% open source. Read all about it in Marco’s release blog. 💥
[UPDATE in Sep 2021]: This blog post was originally written during the PostgreSQL 14 development cycle. The feature discussed is now a candidate for PostgreSQL 15 and the text has been updated to reflect this.
As part of my work on the open source PostgreSQL team at Microsoft, I’ve been developing a new feature for PostgreSQL to track dependencies on collation versions, with help from co-author Julien Rouhaud and many others who have contributed ideas. It’s taken a long time to build a consensus on how to tackle this thorny problem (work I began at EnterpriseDB and continued at Microsoft), and you can read about some of the details and considerations in the commit message below and the referenced discussion thread. We’re not quite done with that yet. It was originally planned for PostgreSQL 14, but some unhandled complications arose so this project is back in the workshop.
commit 257836a75585934cc05ed7a80bccf8190d41e056 Author: Thomas Munro <[email protected]> Date: Mon Nov 2 19:50:45 2020 +1300 Track collation versions for indexes. Record the current version of dependent collations in pg_depend when creating or rebuilding an index. When accessing the index later, warn that the index may be corrupted if the current version doesn't match. Thanks to Douglas Doole, Peter Eisentraut, Christoph Berg, Laurenz Albe, Michael Paquier, Robert Haas, Tom Lane and others for very helpful discussion. Author: Thomas Munro <[email protected]> Author: Julien Rouhaud <[email protected]> Reviewed-by: Peter Eisentraut <[email protected]> (earlier versions) Discussion: https://postgr.es/m/CAEepm%3D0uEQCpfq_%2BLYFBdArCe4Ot98t1aR4eYiYTe%3DyavQygiQ%40mail.gmail.com
In this article I’ll talk about the problem we need to solve—that PostgreSQL indexes can get corrupted by changes in collations that occur naturally over time—and how the new feature will make things better in a future version of PostgreSQL. Plus, you’ll get a bit of background on collations, too.Keep reading