Help Center/ GaussDB/ Developer Guide(Centralized_3.x)/ SQL Optimization/ Hint-based Tuning/ Hint for Adaptive Plan Selection
Updated on 2024-05-07 GMT+08:00
View PDF
Share

Hint for Adaptive Plan Selection

Description

For query statements and DML statements executed in PBE mode, you can add the choose_adaptive_gplan hint to the query to trigger adaptive plan selection.

Syntax

Enable adaptive plan selection for query: 
1
 
choose_adaptive_gplan
  • For SQL statements that are executed in non-PBE mode, setting this hint does not affect the execution mode.
  • This hint takes effect only when the GUC parameter enable_cachedplan_mgr is set to on.

Examples

prepare k as select /*+ choose_adaptive_gplan */ * from t1 where c1=$1 and c2=$2 and c3=$3 and c4=$4;
Parent topic: Hint-based Tuning