Relax overly strict assertion
Ever since its birth, ReorderBufferBuildTupleCidHash() has contained an
assertion that a catalog tuple cannot change Cmax after acquiring one. But
that's wrong: if a subtransaction executes DDL that affects that catalog
tuple, and later aborts and another DDL affects the same tuple, it will
change Cmax. Relax the assertion to merely verify that the Cmax remains
valid and monotonically increasing, instead.
Add a test that tickles the relevant code.
Diagnosed by, and initial patch submitted by: Arseny Sher
Co-authored-by: Arseny Sher
Discussion: https://postgr.es/m/874l9p8hyw.fsf@ars-thinkpad
Branch
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REL9_6_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/db02c179d7f57d3b694670d8e8085812dc1575bd
Modified Files
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contrib/test_decoding/expected/ddl.out | 18 ++++++++++++++++++
contrib/test_decoding/sql/ddl.sql | 13 +++++++++++++
src/backend/replication/logical/reorderbuffer.c | 14 +++++++++-----
3 files changed, 40 insertions(+), 5 deletions(-)