My Oracle Support Banner

OR-Expansion in 19c Causes Slower Executions Plans than in Previous Versions (Doc ID 2747498.1)

Last updated on MAY 21, 2021

Applies to:

Oracle Database - Enterprise Edition - Version 12.2.0.1 to 19.8.0.0.0 [Release 12.2 to 19]
Information in this document applies to any platform.

Symptoms

You upgraded from 11.2 or 12.1, and queries involving OR-expansion are slower in 19c.  The good plan likely contained a CONCATENATION operation, whereas the new plan does not.

Changes

 Upgrade from 11.2 or 12.1 to 19c.

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


My Oracle Support provides customers with access to over a million knowledge articles and a vibrant support community of peers and Oracle experts.