
Trying to attach a table as a partition which is already on the referenced side of a foreign key on the partitioned table that it is being attached to, leads to strange behavior: we try to clone the foreign key from the parent to the partition, but this new FK points to the partition itself, and the mix of pg_constraint rows and triggers doesn't behave well. Rather than trying to untangle the mess (which might be possible given sufficient time), I opted to forbid the ATTACH. This doesn't seem a problematic restriction, given that we already fail to create the foreign key if you do it the other way around, that is, having the partition first and the FK second. Backpatch to all supported branches. Reported-by: Alexander Lakhin <exclusion@gmail.com> Reviewed-by: Tender Wang <tndrwang@gmail.com> Discussion: https://postgr.es/m/18541-628a61bc267cd2d3@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.
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