Call now: 252-767-6166  
Oracle Training Oracle Support Development Oracle Apps

 E-mail Us
 Oracle Articles
New Oracle Articles

 Oracle Training
 Oracle Tips

 Oracle Forum
 Class Catalog

 Remote DBA
 Oracle Tuning
 Emergency 911
 RAC Support
 Apps Support
 Oracle Support

 SQL Tuning

 Oracle UNIX
 Oracle Linux
 Remote s
 Remote plans
 Application Server

 Oracle Forms
 Oracle Portal
 App Upgrades
 SQL Server
 Oracle Concepts
 Software Support

 Remote S


 Consulting Staff
 Consulting Prices
 Help Wanted!


 Oracle Posters
 Oracle Books

 Oracle Scripts

Don Burleson Blog 







ordered Predicates hint Tips

Oracle Tips by Burleson Consulting

July 122, 2015

Using the ordered_predicates hint

The ordered_predicates hint is specified in the WHERE clause of a query and is used to specify the order in which Boolean predicates should be evaluated. In the absence of ordered_predicates, Oracle uses the following steps to evaluate the order of SQL predicates:

  1. Subqueries are evaluated before the outer Boolean conditions in the WHERE clause.
  2. All Boolean conditions without built-in functions or subqueries are evaluated in reverse from the order they are found in the WHERE clause, with the last predicate being evaluated first.
  3. Boolean predicates with built-in functions of each predicate are evaluated in increasing order of their estimated evaluation costs.

You can override these default evaluation rules using the ordered_predicates hint, and your WHERE clause items will then be evaluated in the order that they appear in the query. The ordered_predicates hint is commonly used in cases where a PL/SQL function is used in the WHERE clause of a query. It is also very useful in cases where you know the most restrictive predicates and you want Oracle to evaluate these first.

Usage note:

You cannot use the ordered_predicates hint to preserve the order of predicate evaluation on index keys.

Get the Complete
Oracle SQL Tuning Information 

The landmark book "Advanced Oracle SQL Tuning  The Definitive Reference"  is filled with valuable information on Oracle SQL Tuning. This book includes scripts and tools to hypercharge Oracle 11g performance and you can buy it for 30% off directly from the publisher.





Burleson is the American Team

Note: This Oracle documentation was created as a support and Oracle training reference for use by our DBA performance tuning consulting professionals.  Feel free to ask questions on our Oracle forum.

Verify experience! Anyone considering using the services of an Oracle support expert should independently investigate their credentials and experience, and not rely on advertisements and self-proclaimed expertise. All legitimate Oracle experts publish their Oracle qualifications.

Errata?  Oracle technology is changing and we strive to update our BC Oracle support information.  If you find an error or have a suggestion for improving our content, we would appreciate your feedback.  Just  e-mail:  

and include the URL for the page.


Burleson Consulting

The Oracle of Database Support

Oracle Performance Tuning

Remote DBA Services


Copyright © 1996 -  2017

All rights reserved by Burleson

Oracle ® is the registered trademark of Oracle Corporation.

Remote Emergency Support provided by Conversational