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 







  ORA-01502: index or partition of such index is in usable state tips 

Oracle Database Tips by Donald BurlesonApril 4, 2015

The Oracle docs note this on the ORA-01502 error:


ORA-01502: index "string.string" or partition of such index is in unusable state

Cause: An attempt has been made to access an index or index partition that has been marked unusable by a direct load or by a DDL operation  

Action: DROP the specified index, or REBUILD the specified index, or REBUILD the unusable index partition

The ORA-01502 error can be easily fixed by issuing the alter index index_name rebuild partition partition_name;

To learn how to rebuild unusable partitioned indexes see these notes on Oracle index partition management.

ORA-01502 and skip_unusable_indexes

In previous releases of Oracle, the skip_unusable_indexes parameter could only be used at session level and the default value was False. Now, you will be able to set this parameter at session level and instance level as well.

By setting the value of the skip_unusable_indexes=true, the optimizer selects an execution plan that does not utilize unusable indexes, preventing ORA-01502 errors.

However, when you skip an index you risk getting a sub-optimal SQL execution plan. And since the SQL statement generates no error, the end-user is unaware that the optimizer has chosen a plan that was less than optimal and only notices excessive response time.

When you skip an unusable index, the database records an error message in the alert log file whenever an index is marked unusable.

ORA-01502 and sqlldr

The ORA-01502 can happen while using SQL Loader.  They continued to have problems with ORA-01502 (being thrown along with ORA-01452), even after trying to, "load the same record twice (Just 2 lines in the data file to be loaded) accepted that...and change the length of the last field (from 3 to 4), but when I see the data using select statement they look exactly the same!!!"

After one quick reply to simply fix the duplicate data, Burleson offered these easy to follow steps concerning row duplication detection:

1 - Drop the offending index and load the data.

2 - Run a script to detect duplicate rows:

3 - Remove the rows and rebuild the index

Need another helpful link? Try this concerning unusable indexes:


Oracle Training from Don Burleson 

The best on site "Oracle training classes" are just a phone call away! You can get personalized Oracle training by Donald Burleson, right at your shop!

Oracle training



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 -  2020

All rights reserved by Burleson

Oracle ® is the registered trademark of Oracle Corporation.



Oracle Training at Sea
oracle dba poster

Follow us on Twitter 
Oracle performance tuning software 
Oracle Linux poster