MERGE ... DO NOTHING: require SELECT privileges
Verify that a user running MERGE with a DO NOTHING clause has
privileges to read the table, even if no columns are referenced. Such
privileges were already required if the ON clause or any of the WHEN
conditions referenced any column at all, so there's no functional change
in practice.
This change fixes an assertion failure in the case where no column is
referenced by the command and the WHEN clauses are all DO NOTHING.
Backpatch to 15, where MERGE was introduced.
Reported-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/4d65a385-7efa-4436-a825-0869f89d9d92@postgrespro.ru
Branch
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REL_16_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/a3f5d2056ceba95d94607be3138fa52499a957e6
Modified Files
--------------
src/backend/parser/parse_merge.c | 7 ++++++-
src/test/regress/expected/merge.out | 10 ++++++++++
src/test/regress/sql/merge.sql | 11 +++++++++++
3 files changed, 27 insertions(+), 1 deletion(-)