Re: Object table - Changes to object question confirmation

From: Daniel Morgan <damorgan_at_x.washington.edu>
Date: Wed, 07 Jul 2004 06:22:08 -0700
Message-ID: <1089206565.474730@yasure>

Galen Boyer wrote:

> On Tue, 06 Jul 2004, damorgan_at_x.washington.edu wrote:
> 

>>Luch wrote:
>>
>>
>>>Did some research (and tried it myself) and this is what I
>>>understand from object tables (or tables that have one if its
>>>fields being an object type) in 9i.... In order to make a
>>>change later on to the object, any table that is using it
>>>(wheter it is one field or an object table) would first have
>>>to be dropped. Otherwise it gives dependency errors. Is this
>>>correct? This doesn't make sense to me... How can it be
>>>expected that an object can never later be changed (adding
>>>another field, increasing a varchar2 field, etc). This makes
>>>them "useless" to me to want to use an object in a table. -
>>>Replace nospam with hotmail for e-mail.
>>
>>I think correct but your assumption about it being useless is
>>incorrect.
>>
>>You are supposed to data model your schema then code. If you
>>hava some overwhelming need to redefine objects on-the-fly it
>>only demonstrates a lack of putting together proper
>>specifications before you started banging out code.

> 
> 
> I've never once been on a project where the datamodel didn't
> change during the lifetime of the project.  I guess you have. 

Data model ... yes. But data types ... no.

As someone above alluded to ... you don't change VARCHAR2 to NUMBER or DATE to CLOB. We are talking here about user defined data types acting as columns. Or at least that was my assumption.

-- 
Daniel Morgan
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Received on Wed Jul 07 2004 - 08:22:08 CDT