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my-ship-it
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LGTM.
It is an existing bug, which is introduced by PG 16 merge.
leborchuk
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LGTM, clear bug, just should be fixed
MERGE into a DISTRIBUTED REPLICATED table did not broadcast the source relation, so each segment merged only the source rows stored locally. The replicas diverged and the reported row count was wrong. Treat MERGE like UPDATE/DELETE when flagging a replicated result relation (upd_del_replicated_table), so the join broadcasts the source to all segments. Also reject volatile functions in MERGE actions on replicated tables. The existing check only looked at the subplan targetlist, but MERGE action expressions are kept in mergeActionLists, so e.g. "UPDATE SET v = random()" was accepted and the replicas diverged.
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MERGE into a DISTRIBUTED REPLICATED table did not broadcast the source relation, so each segment merged only the source rows stored locally. The replicas diverged and the reported row count was wrong.
Treat MERGE like UPDATE/DELETE when flagging a replicated result relation (upd_del_replicated_table), so the join broadcasts the source to all segments.
Also reject volatile functions in MERGE actions on replicated tables. The existing check only looked at the subplan targetlist, but MERGE action expressions are kept in mergeActionLists, so e.g. "UPDATE SET v = random()" was accepted and the replicas diverged.
Fixes #ISSUE_Number
What does this PR do?
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Breaking Changes
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make installcheckmake -C src/test installcheck-cbdb-parallelImpact
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