My Oracle Support Banner

Data Dictionary View Queries are Slow - Potential Solutions (Doc ID 222671.1)

Last updated on AUGUST 04, 2018

Applies to:

Oracle Database - Enterprise Edition - Version 6.0.0.0 and later
Oracle Database - Standard Edition - Version 7.0.16.0 and later
Oracle Database - Personal Edition - Version 7.1.4.0 and later
Information in this document applies to any platform.

Purpose

This article outlines the basic steps to take when queries against Data Dictionary Views

Scope

Prior to Oracle 10g, the data dictionary was optimized to use the Rule-Based Optimizer (RBO). By default the dictionary had no statistics and queries used RBO or CBO (Cost Based Optimizer) if hints were present in the underlying dictionary views. With large databases, this tended not to scale and so some queries against the data dictionary performed sub-optimally. 

In later releases, enhancements were made to improve the performance. This document outlines some of these and also available workarounds and their advantages and disadvantages in the case of problems.


Details

To view full details, sign in with your My Oracle Support account.

Don't have a My Oracle Support account? Click to get started!


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