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

 E-mail Us
 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 







Oracle select for update tips

Oracle Tips by Burleson Consulting

January 1, 2013

  I am having trouble with locking using select for update, and I want to know how to prevent deadlocks while holding row locks.  Are there alternatives to select for update?

Answer:  The select for update has many issues, and select for update is especially dangerous when a transaction aborts and a "zombie" process continues to hold rows locks.

The select for update is the bane of the DBA, and there are many better alternatives to select for update.

The select for update is not a good locking strategy because there are many things that can go wrong. 

Instead of select for update, savvy Oracle developers will adopt alternatives mechanisms like:

1 - On initial read, save the row contents in RAM.

2 - Re-read upon update commit time.  If the rows has not changed since the initial read, update the row.

3 - If row has changed re-read again, process and update the row

See my related notes on select for update clause:

If you like Oracle tuning, you may enjoy my bestselling book Oracle Tuning: The Definitive Reference", with over 900 pages of BC's favorite tuning tips & scripts. 

You can buy it direct from the publisher for 30%-off and get instant access to the code depot of Oracle tuning scripts.




oracle dba poster

Oracle performance tuning software 
Oracle Linux poster


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 -  2014

All rights reserved by Burleson

Oracle ? is the registered trademark of Oracle Corporation.