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The original setup for dependencies of partitioned objects had serious problems: 1. It did not verify that a drop cascading to a partition-child object also cascaded to at least one of the object's partition parents. Now, normally a child object would share all its dependencies with one or another parent (e.g. a child index's opclass dependencies would be shared with the parent index), so that this oversight is usually harmless. But if some dependency failed to fit this pattern, the child could be dropped while all its parents remain, creating a logically broken situation. (It's easy to construct artificial cases that break it, such as attaching an unrelated extension dependency to the child object and then dropping the extension. I'm not sure if any less-artificial cases exist.) 2. Management of partition dependencies during ATTACH/DETACH PARTITION was complicated and buggy; for example, after detaching a partition table it was possible to create cases where a formerly-child index should be dropped and was not, because the correct set of dependencies had not been reconstructed. Less seriously, because multiple partition relationships were represented identically in pg_depend, there was an order-of-traversal dependency on which partition parent was cited in error messages. We also had some pre-existing order-of-traversal hazards for error messages related to internal and extension dependencies. This is cosmetic to users but causes testing problems. To fix #1, add a check at the end of the partition tree traversal to ensure that at least one partition parent got deleted. To fix #2, establish a new policy that partition dependencies are in addition to, not instead of, a child object's usual dependencies; in this way ATTACH/DETACH PARTITION need not cope with adding or removing the usual dependencies. To fix the cosmetic problem, distinguish between primary and secondary partition dependency entries in pg_depend, by giving them different deptypes. (They behave identically except for having different priorities for being cited in error messages.) This means that the former 'I' dependency type is replaced with new 'P' and 'S' types. This also fixes a longstanding bug that after handling an internal dependency by recursing to the owning object, findDependentObjects did not verify that the current target was now scheduled for deletion, and did not apply the current recursion level's objflags to it. Perhaps that should be back-patched; but in the back branches it would only matter if some concurrent transaction had removed the internal-linkage pg_depend entry before the recursive call found it, or the recursive call somehow failed to find it, both of which seem unlikely. Catversion bump because the contents of pg_depend change for partitioning relationships. Patch HEAD only. It's annoying that we're not fixing #2 in v11, but there seems no practical way to do so given that the problem is exactly a poor choice of what entries to put in pg_depend. We can't really fix that while staying compatible with what's in pg_depend in existing v11 installations. Discussion: https://postgr.es/m/CAH2-Wzkypv1R+teZrr71U23J578NnTBt2X8+Y=Odr4pOdW1rXg@mail.gmail.com |
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authentication | ||
examples | ||
isolation | ||
kerberos | ||
ldap | ||
locale | ||
mb | ||
modules | ||
perl | ||
recovery | ||
regress | ||
ssl | ||
subscription | ||
thread | ||
Makefile | ||
README |
PostgreSQL tests ================ This directory contains a variety of test infrastructure as well as some of the tests in PostgreSQL. Not all tests are here -- in particular, there are more in individual contrib/ modules and in src/bin. Not all these tests get run by "make check". Check src/test/Makefile to see which tests get run automatically. authentication/ Tests for authentication examples/ Demonstration programs for libpq that double as regression tests via "make check" isolation/ Tests for concurrent behavior at the SQL level locale/ Sanity checks for locale data, encodings, etc mb/ Tests for multibyte encoding (UTF-8) support modules/ Extensions used only or mainly for test purposes, generally not suitable for installing in production databases perl/ Infrastructure for Perl-based TAP tests recovery/ Test suite for recovery and replication regress/ PostgreSQL's main regression test suite, pg_regress ssl/ Tests to exercise and verify SSL certificate handling subscription/ Tests for logical replication thread/ A thread-safety-testing utility used by configure