19c: Huge Performance Degradation On Second Execution For A Query When Statistics Feedback Activates And OPTIMIZER_ADAPTIVE_STATISTICS Is TRUE
(Doc ID 3080280.1)
Last updated on APRIL 09, 2025
Applies to:
Oracle Database - Enterprise Edition - Version 19.20.0.0.0 to 19.26.0.0.0 [Release 19]Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Gen 2 Exadata Cloud at Customer - Version N/A and later
Oracle Cloud Infrastructure - Exadata Cloud Service - Version N/A and later
Information in this document applies to any platform.
Symptoms
Huge Performance degradation is noticed on second execution of a query when OPTIMIZER_ADAPTIVE_STATISTICS is TRUE and Statistics Feedback gets activated:
Changes
OPTIMIZER_ADAPTIVE_STATISTICS parameter was set to TRUE at system level
Cause
To view full details, sign in with your My Oracle Support account. |
|
Don't have a My Oracle Support account? Click to get started! |
In this Document
| Symptoms |
| Changes |
| Cause |
| Solution |
| References |