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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Index-Organized Table experiences
I've been using IOTs, though not for intersection entities.
I had a problem (in Oracle 8.1.5) with "on delete cascade" foreign key
(IOT as a child table). Had to implement "on delete" trigger on parent
table instead of foreign key.
Don't know, if it's fixed in 10g.
Igor Neyman, OCP DBA
ineyman_at_perceptron.com
-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Daniel Fink
Sent: Wednesday, April 28, 2004 9:15 AM
To: oracle-l_at_freelists.org
Subject: Index-Organized Table experiences
We are looking to implement IOTs for a couple of intersection entities in a 10g db. I would like to hear from those brave enough to actually use IOTs what is the good, the bad and the ugly.
example:
Employee (heap table)
Project (heap table)
There is a many-to-many relationship between the tables (1 employee can be on many projects and 1 project can have many employees).
The emp_project table is the intersection entity containing emp_id and project_id as the only columns. There are FK constraints on each of the columns. The combination of emp_id and project_id is unique.
This situation *sounds* like the right one for an IOT, otherwise we would have 1 table and 2 indexes (1 on each column).
My main concerns are:
1) Integrity/performance
2) Locking behavior (do I need to adhere to the traditional
"index all foreign keys" rule to prevent excessive locking?)
3) Any especially nasty gotchas
Thanks,
Daniel
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