Обсуждение: pgsql: Fix assignment to array of domain over composite, redux.

Fix assignment to array of domain over composite, redux.

Commit 3e310d837 taught isAssignmentIndirectionExpr() to look through
CoerceToDomain nodes.  That's not sufficient, because since commit
04fe805a1 it's been possible for the planner to simplify
CoerceToDomain to RelabelType when the domain has no constraints
to enforce.  So we need to look through RelabelType too.

Per bug #17897 from Alexander Lakhin.  Although 3e310d837 was
back-patched to v11, it seems sufficient to apply this change
to v12 and later, since 04fe805a1 came in in v12.

Dmitry Dolgov

Discussion: https://postgr.es/m/17897-4216c546c3874044@postgresql.org

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9b104a27c72754e9a6a8043ad7e710c8c386a8db

Modified Files
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src/backend/executor/execExpr.c      | 10 ++++++++--
src/test/regress/expected/domain.out |  9 +++++++++
src/test/regress/sql/domain.sql      |  4 ++++
3 files changed, 21 insertions(+), 2 deletions(-)