Fix assertion failure in getNdvBySegHeapTuple for empty partitions.#1599
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zhangwenchao-123 wants to merge 1 commit intoapache:mainfrom
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Fix assertion failure in getNdvBySegHeapTuple for empty partitions.#1599zhangwenchao-123 wants to merge 1 commit intoapache:mainfrom
zhangwenchao-123 wants to merge 1 commit intoapache:mainfrom
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When merging leaf partition statistics for a partitioned table, getNdvBySegHeapTuple could hit Assert(valuetype == FLOAT8OID) if a partition had relTuples == 0 and its pg_statistic entry lacked a valid STATISTIC_KIND_NDV_BY_SEGMENTS slot (or the slot had an unexpected element type). The original guard condition only handled two cases: 1. Non-empty partition with NDV value == 0 2. Non-empty partition without NDV_BY_SEGMENTS It missed the case where an empty partition (relTuples == 0) has a pg_statistic entry but no valid FLOAT8OID NDV_BY_SEGMENTS slot, causing the code to fall through to the assertion. Fix by checking valuetype != FLOAT8OID upfront: skip empty partitions gracefully, and mark non-empty partitions as invalid. Authored-by: Zhang Wenchao zwcpostgres@gmail.com
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| Assert(ndvbsSlots[i]->valuetype == FLOAT8OID); |
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This assert may keep here.
| break; | ||
| } | ||
| } | ||
| return valid; |
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All of the ndvbsSlots could be release if the valid becomes false. On the other side, the ndvbsSlots and its pointer array could be also freed in aggregate_leaf_partition_ndvbs no matter it's valid or not.
yjhjstz
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Mar 9, 2026
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| Assert(ndvbsSlots[i]->valuetype == FLOAT8OID); | ||
| Assert(ndvbsSlots[i]->nvalues == 1); | ||
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if (ndvbsSlots[i]->nvalues != 1)
{
valid = false;
break;
}
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When merging leaf partition statistics for a partitioned table, getNdvBySegHeapTuple could hit Assert(valuetype == FLOAT8OID) if a partition had relTuples == 0 and its pg_statistic entry lacked a valid STATISTIC_KIND_NDV_BY_SEGMENTS slot (or the slot had an unexpected element type).
The original guard condition only handled two cases:
Fix by checking valuetype != FLOAT8OID upfront: skip empty partitions gracefully, and mark non-empty partitions as invalid.
Fixes #ISSUE_Number
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Breaking Changes
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make installcheckmake -C src/test installcheck-cbdb-parallelImpact
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