Re: Order of fields in a table.

From: Daniel Morgan <damorgan_at_exxesolutions.com>
Date: Fri, 04 Jul 2003 15:15:24 -0700
Message-ID: <3F05FC7C.D6F813A@exxesolutions.com>

Quarkman wrote:

> "Daniel Morgan" <damorgan_at_exxesolutions.com> wrote in message
> news:3F059BF9.DC7B9833_at_exxesolutions.com...
> > ben brugman wrote:
> >
> > > Order of fields in a table.
> > >
> > > Do you insert fields in a table, or do you
> > > append all new fields to the end.
> > >
> > > I prefer to insert the fields, but inserting a field
> > > can be cumbersome and takes some time
> > > in a real live database. I am aware that applications
> > > should not use any order, but there are also humans
> > > seeing the order of the fields in the database.
> > > (Checking which fields exist and using general utilities
> > > etc.).
> > >
> > > What is common in your world, adding or inserting ?
> > >
> > > ben brugman.
> >
> > Time spent worrying about the ordering of columns in a relational table
> > are just wasted.
> >
> > If you make more than one change a year there is something wrong with
> > the design process.
> > --

>

> Not entirely true, actually.

>

> If you use LONG datatypes, they should sensibly be the last columns in the
> table, because access to them is sequential and they are always stored
> in-line with your other data (meaning getting at that other data would
> require you to wade through the entire LONG if it was stored in a column
> positioned before it).

>

> OK, so LONGs are deprecated and LOBS don't suffer the same problem because
> they are stored out-of-line. So what about IOTs then?

>

> <snipped>

>

> (For heap tables, I agree with you, though).

>

> ~QM

>


> > Daniel Morgan

> > http://www.outreach.washington.edu/extinfo/certprog/oad/oad_crs.asp

> > damorgan_at_x.washington.edu

> > (replace 'x' with a 'u' to reply)

> >
> >

Of course if you are developing a new application using LONG you have demonstrated that you don't read and/or follow advice from Oracle as to support for LONG and LONG RAW in the future.

Anyone building a new table with LONG ... deserves what they get and CLOBs don't have this problem nor do IOT's.

--
Daniel Morgan
http://www.outreach.washington.edu/extinfo/certprog/oad/oad_crs.asp
damorgan_at_x.washington.edu
(replace 'x' with a 'u' to reply)

Received on Fri Jul 04 2003 - 17:15:24 CDT