Fix: ERROR: too many sample rows received from gp_acquire_sample_rows #1294
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jiaqizho
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Aug 8, 2025
my-ship-it
approved these changes
Aug 12, 2025
jiaqizho
approved these changes
Aug 13, 2025
…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?
Type of Change
Breaking Changes
Test Plan
make installcheckmake -C src/test installcheck-cbdb-parallelImpact
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