Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.server -> Re: Oracle - Column Order

Re: Oracle - Column Order

From: Billy <vslabs_at_onwe.co.za>
Date: 18 Oct 2005 22:32:49 -0700
Message-ID: <1129699968.992912.233610@g47g2000cwa.googlegroups.com>


Sybrand Bakker wrote:

> >But then this not something that the OP has likely in mind?
> >Conceptually - agree whole heartedly: the order of columns in a table
> >has *NO* significance to application development, developers and
> >end-users.
>
> Too bad the column order actually DOES matter, as it takes time to
> traverse a record: the exact position of a column in a record can only
> be retrieved by traversing all previous columns.

Not talking about physically Sybrand, but conceptually. Applications should not be coded in such a way to expect column 1 to always contain CUST_ID, column 2 containing FOO_1, etc.

Or expect the PK index to always be named PE_<tablelename>. Or views to be qualified with a V_<viewname>. Or block sizes of always 8KB. Or indexes to be in a separate tablespaces. Etc.

Column order does -not- matter from an application viewpoint. Physical characteristics of the database has no bearing at all to the application. If it does, the application is flawed and the smallest physical database change will break the application.

The only people that should be concerned with the physical order of columns and stuff at that level, are people like you and me. DBAs. Not developers. Not end-users. And the only recommendation I've ever run across from Oracle in Oracle documentation ito column order is to put the most frequently null column at the end of a row so that the column label does not need to be stored with the row on the data block. If you know of any more in this regard, I will appreciate the Oracle documentation references.

--
Billy
Received on Wed Oct 19 2005 - 00:32:49 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US