From: tk...@us.oracle.com (Thomas Kyte)
Subject: Re: how to alter table columns:
Date: 1999/08/11
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A copy of this was sent to "Rauno Seppanen" <rauno.seppa...@icon.fi>
(if that email address didn't require changing)
On Wed, 11 Aug 1999 19:10:11 GMT, you wrote:

>>1) you cannot in any version of Oracle rename a column.  In Oracle8i,
>release
>>8.1 you can drop a column so I suppose the steps of:

[snip]

>
>What do you think about updateing sys.col$ ?

I think it is a hugely *BAD* terrible idea.  Words cannot describe how bad it
could be.

>You need to flush (or shutdown and restart database)
>to see the change of the column. I did't once and it has worked fine.

you have procedures that should be invalid (but aren't) out there.  they could
and will raise internal errors (these procedures that reference this old column
*should* work but they won't and the system won't understand why)

you have views that should be invalid (but aren't) out there.... same as above.
I see lots of internal errors in your future.

you have constraints that reference this now non-existent column.  they can and
will raise internal errors.

don't even want to think what this would do to replication.

who knows what hidden side effects may occur.  I know of real side effects, some
above, but that is not an inclusive list.  

bottom line -- do it and you are on you own. 


[snip]

>


-- 
See http://govt.us.oracle.com/~tkyte/ for my columns 'Digging-in to Oracle8i'...
Current article is "Part I of V, Autonomous Transactions" updated June 21'st
 
Thomas Kyte                   tk...@us.oracle.com
Oracle Service Industries     Reston, VA   USA

Opinions are mine and do not necessarily reflect those of Oracle Corporation