Wiki / Configuration Parameters

Enables or disables the query planner's use of partitionwise grouping or aggregation, which allows grouping or aggregation on partitioned tables to be performed separately for each partition. If the GROUP BY clause does not include the partition keys, only partial aggregation can be performed on a per-partition basis, and finalization must be performed later. With this setting enabled, the number of nodes whose memory usage is restricted by work_mem appearing in the final plan can increase linearly according to the number of partitions being scanned. This can result in a large increase in overall memory consumption during the execution of the query. Query planning also becomes significantly more expensive in terms of memory and CPU. The default value is off.

English manual coverage begins with PostgreSQL 7.4. Source history and runtime observations have their own recorded version boundaries.

boot val

off

category

Query Tuning / Planner Method Configuration

context

user

documented

true

enumvals

Unknown

extra desc

Unknown

lang

en

max val

Unknown

metadata version

18

min val

Unknown

name

enable_partitionwise_aggregate

short desc

Enables partitionwise aggregation and grouping.

source

pg-settings-source-snapshot

unit

Unknown

vartype

bool