Q
Problem solve Get help with specific problems with your technologies, process and projects.

Entity-Attribute-Value constraints

SQL expert Rudy Limeback explains the entity-attribute-value model.

I have some validation rules. There are two tables, NODE and METANODE. Here the METANODE column SUBTYPE will depend...

on the value of the NODE column NODETYPE. So, if NODETYPE of NODE has a value of 'Role' then SUBTYPE of METANODE might have the value 'Process'.

NODE               METANODE
--------------     ---------------   
NODETYPE : Role    SUBTYPE : Process

How can I put a constraint for this?

This is one of three questions this week, to which, I'm afraid, the answer is no.

[The others were A running total and SQL to update the header records?]

No, I don't think you can declare a constraint.

This looks very much like the entity-attribute-value model. I personally would avoid it. Here are some links for further opinions:

Good luck.

This was last published in April 2008

Dig Deeper on Oracle development languages

PRO+

Content

Find more PRO+ content and other member only offers, here.

Have a question for an expert?

Please add a title for your question

Get answers from a TechTarget expert on whatever's puzzling you.

You will be able to add details on the next page.

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

-ADS BY GOOGLE

SearchDataManagement

SearchBusinessAnalytics

SearchSAP

SearchSQLServer

TheServerSide

SearchDataCenter

SearchContentManagement

SearchFinancialApplications

Close