Fix MERGE's test for unreachable WHEN clauses.
The former code would only detect an unreachable WHEN clause if it had
an AND condition. Fix, so that unreachable unconditional WHEN clauses
are also detected.
Back-patch to v15, where MERGE was added.
Discussion: https://postgr.es/m/CAEZATCVQ=7E2z4cSBB49jjeGGsB6WeoYQY32NDeSvcHiLUZ=ow@mail.gmail.com
Branch
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REL_15_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/38255f2d0059a101c3fb791d6523a9e66e55aa66
Modified Files
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src/backend/parser/parse_merge.c | 6 +++---
src/test/regress/expected/merge.out | 2 +-
src/test/regress/sql/merge.sql | 2 +-
3 files changed, 5 insertions(+), 5 deletions(-)