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 







Linda Webb

Got breaking Oracle news?    Burleson Consulting Oracle News

Click here for more Oracle News Headlines


See Oracle Collections, Nested Tables and VARRAY Columns

Oracle collections are a non-relational extension of Oracle that allow non first-normal form representation of data, either via repeating groups of table columns addressed with subscripts (e.g. select test_score(3) from student;) or via the non-relation "nested table" construct.

Below, Lewis Cunningham has an excellent overview and examples of these Oracle collection features: 

Cunningham shows examples of VARRAY table definition and queries:

2 /

------------------------------ ---------
Lewis 01-JAN-60
ADDRESSES_V('Line 1', 'Line 2', 'Line 3')
ADDRESSES_N('Line 1', 'Line 2', 'Line 3')

Cunningham also shows Oracle nested table definitions and usage. The author concludes about the choice between nested tables and VARRAY tables:

"Now I guess we should talk about when to use a particular type of collection. In PL/SQL, for the most part, it's a matter of preference. If you know you have a maximum, use VARRAY. The choice between Nested Table and Associative Table is not as clear cut. In general, I use Nested Table instead of Associative Tables unless I am indexing the array with a VARCHAR2.

In SQL, it's a different subject. Of course, you cannot use an Associative table at all in SQL so your choices are down to Nested Table or Varray. I rarely, if ever, use nested tables or varrays in a relational table. I prefer to create a normal table and use foreign keys."


Oracle Training at Sea
oracle dba poster

Follow us on Twitter 
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 -  2017

All rights reserved by Burleson

Oracle ® is the registered trademark of Oracle Corporation.

Remote Emergency Support provided by Conversational