Fix aoco_relation_size() using wrong snapshot to read pg_aocsseg#1668
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yjhjstz merged 1 commit intoapache:mainfrom Apr 9, 2026
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Fix aoco_relation_size() using wrong snapshot to read pg_aocsseg#1668yjhjstz merged 1 commit intoapache:mainfrom
yjhjstz merged 1 commit intoapache:mainfrom
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reshke
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Apr 9, 2026
aoco_relation_size() used GetLatestSnapshot() to read pg_aocsseg catalog metadata. During ALTER TABLE SET DISTRIBUTED BY on AOCO tables, the reader gang's GetLatestSnapshot() cannot see pg_aocsseg rows written by the writer gang within the same distributed transaction (uncommitted local xid), causing the function to return 0 bytes. This led to relpages=0 being passed to vac_update_relstats() alongside a non-zero totalrows from sampling (which correctly uses GetCatalogSnapshot()), triggering an assertion failure: FailedAssertion: "Gp_role == GP_ROLE_UTILITY", vacuum.c:1738 Fix by passing NULL to GetAllAOCSFileSegInfo() so that systable_beginscan() uses GetCatalogSnapshot() internally, consistent with appendonly_relation_size() for AO row tables.
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The inconsistency between relpages=0 (from the wrong snapshot) and num_tuples=56 (from the correct catalog snapshot) hits an assertion in vac_update_relstats() that assumed this
combination — an AO table with zero pages but non-zero tuples — could only occur in utility mode. Since the QE runs in GP_ROLE_EXECUTE, the assertion Gp_role == GP_ROLE_UTILITY fails
and the segment process aborts.
Fix by passing NULL to GetAllAOCSFileSegInfo() so that systable_beginscan() uses GetCatalogSnapshot() internally, consistent with appendonly_relation_size() for AO row tables.
Fixes #ISSUE_Number
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make installcheckmake -C src/test installcheck-cbdb-parallelImpact
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