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RE: How to use the Unused Column?

From: Mercadante, Thomas F \(LABOR\) <>
Date: Tue, 19 Dec 2006 14:45:14 -0500
Message-ID: <ABB9D76E187C5146AB5683F5A07336FFE08973@EXCNYSM0A1AJ.nysemail.nyenet>

Jacques and Michael,

What I meant is from a development point of view, dropping a column and then adding it back in after the fact isn't that expensive to do.

Sure, if you have a huge table this is a big piece of maintenance on a production system

But the question was from a development point of view with the developer thinking he/she was saving some work or something by marking the column unused and then hoping to get it back again.


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-----Original Message-----

From: [] On Behalf Of Jacques Kilchoer Sent: Tuesday, December 19, 2006 2:31 PM To:
Subject: RE: How to use the Unused Column?

"Dropping a column is not a significant event" - isn't Oracle rewriting every used block in the table?

-----Message d'origine-----

De : [] De la part de Mercadante, Thomas F (LABOR) Envoyé : mardi, 19. décembre 2006 11:00
À :; Objet : RE: How to use the Unused Column?


Drop the column when they tell you to and then add it back in later if they need it.

Dropping a column is not a significant event. Neither is adding a column. So just do both or either and tell you developer to stop reading the docs so much and get back to work. :)

-----Original Message-----

Sent: Tuesday, December 19, 2006 12:19 PM To:
Subject: How to use the Unused Column?

One of our developer has asked this question.

"In our project we plan to drop some columns as we anticipate not to use these columns. We do not want to drop the columns completely out of the database and completely lose them, instead we would like to use the unused columns feature in Oracle 10g. From the documentation I have read so far, I could not find anything that says we can retrieve an unused column and remove the unused mark against the column making it available for use"

The development team would like to re-use the column if needed in the future. Is there a way to do it or Once you set it unused you can't get the column and data back?

We are at on HP-UX 11.11.
-- Received on Tue Dec 19 2006 - 13:45:14 CST

Original text of this message