mirror of
https://github.com/postgres/postgres.git
synced 2025-05-28 05:21:27 +03:00
4ae09c59d6
When a partitioned table has an index that doesn't support a constraint, but a partition has an equivalent index that does, then a DETACH operation would misbehave: a crash in assertion-enabled systems (because we fail to find the constraint in the parent that we expect to), or a broken coninhcount value (-1) in production systems (because we blindly believe that we've successfully detached the parent). While we should reject an ATTACH of a partition with such an index, we have failed to do so in existing releases, so adding an error in stable releases might break the (unlikely) existing applications that rely on this behavior. At this point I don't even want to reject them in master, because it'd break pg_upgrade if such databases exist, and there would be no easy way to fix existing databases without expensive index rebuilds. (Later on we could add ALTER TABLE ... ADD CONSTRAINT USING INDEX to partitioned tables, which would allow the user to fix such patterns. At that point we could add more restrictions to prevent the problem from its root.) Also, add a test case that leaves one table in this condition, so that we can verify that pg_upgrade continues to work if we later decide to change the policy on the master branch. Backpatch to all supported branches. Co-authored-by: Tender Wang <tndrwang@gmail.com> Reported-by: Alexander Lakhin <exclusion@gmail.com> Reviewed-by: Tender Wang <tndrwang@gmail.com> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/18500-62948b6fe5522f56@postgresql.org
PostgreSQL Database Management System ===================================== This directory contains the source code distribution of the PostgreSQL database management system. PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.