Fix multiple assignments to a column of a domain type.
We allow INSERT and UPDATE commands to assign to the same column more than
once, as long as the assignments are to subfields or elements rather than
the whole column. However, this failed when the target column was a domain
over array rather than plain array. Fix by teaching process_matched_tle()
to look through CoerceToDomain nodes, and add relevant test cases.
Also add a group of test cases exercising domains over array of composite.
It's doubtless accidental that CREATE DOMAIN allows this case while not
allowing straight domain over composite; but it does, so we'd better make
sure we don't break it. (I could not find any documentation mentioning
either side of that, so no doc changes.)
It's been like this for a long time, so back-patch to all supported
branches.
Discussion: https://postgr.es/m/4206.1499798337@sss.pgh.pa.us
Branch
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REL9_6_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/123368061188ebc8dc99346be2167e3f7a7b618c
Modified Files
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src/backend/rewrite/rewriteHandler.c | 31 ++++++++++
src/test/regress/expected/domain.out | 110 +++++++++++++++++++++++++++++++++--
src/test/regress/sql/domain.sql | 48 +++++++++++++++
3 files changed, 185 insertions(+), 4 deletions(-)