Wiki / Configuration Parameters

Prepared statements (either explicitly prepared or implicitly generated, for example by PL/pgSQL) can be executed using custom or generic plans. Custom plans are made afresh for each execution using its specific set of parameter values, while generic plans do not rely on the parameter values and can be re-used across executions. Thus, use of a generic plan saves planning time, but if the ideal plan depends strongly on the parameter values then a generic plan may be inefficient. The choice between these options is normally made automatically, but it can be overridden with plan_cache_mode. The allowed values are auto (the default), force_custom_plan and force_generic_plan. This setting is considered when a cached plan is to be executed, not when it is prepared. For more information see PREPARE.

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

boot val

auto

category

Query Tuning / Other Planner Options

context

user

documented

true

enumvals

auto, force_generic_plan, force_custom_plan

extra desc

Prepared statements can have custom and generic plans, and the planner will attempt to choose which is better. This can be set to override the default behavior.

lang

en

max val

Unknown

metadata version

18

min val

Unknown

name

plan_cache_mode

short desc

Controls the planner's selection of custom or generic plan.

source

pg-settings-source-snapshot

unit

Unknown

vartype

enum