Fix: ERROR: too many sample rows received from gp_acquire_sample_rows#1294
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yjhjstz merged 1 commit intoapache:mainfrom Aug 13, 2025
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Fix: ERROR: too many sample rows received from gp_acquire_sample_rows#1294yjhjstz merged 1 commit intoapache:mainfrom
yjhjstz merged 1 commit intoapache:mainfrom
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…sticsRows to QD
In `do_analyze_rel`, the function `ComputeExtStatisticsRows` calculates the minimum
number of sample rows needed for extended statistics (e.g., dependencies, ndistinct).
This calculation is only meaningful and required on the Query Dispatcher (QD), since
only the QD is responsible for coordinating the final extended statistics generation.
Previously, all segments (including QEs) executed this logic, resulting in excessive
sampling. For large tables, this caused the QD to receive more rows than it can handle,
leading to the error:
ERROR: too many sample rows received from gp_acquire_sample_rows
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In
do_analyze_rel, the functionComputeExtStatisticsRowscalculates the minimum number of sample rows needed for extended statistics (e.g., dependencies, ndistinct).This calculation is only meaningful and required on the Query Dispatcher (QD), since only the QD is responsible for coordinating the final extended statistics generation.
Previously, all segments (including QEs) executed this logic, resulting in excessive sampling. For large tables, this caused the QD to receive more rows than it can handle, leading to the error:
Fixes #1293
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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