Re: Mixing OO and DB
Date: Wed, 5 Mar 2008 15:02:36 -0500
"Marshall" <marshall.spight_at_gmail.com> wrote in message
> On Mar 5, 6:21 am, "Brian Selzer" <br..._at_selzer-software.com> wrote:
>> How is that different from denormalization? Updates still have to be
>> in a denormalized schema. Of course, instead of updating one row, it may
>> necessary to update hundreds or even thousands of rows due to the
>> inherent in a denormalized schema. With a materialized view, those
>> become a refresh of the view, which can happen independent of the update.
>> The only substantive difference I can see here is that queries can still
>> satisfied by using the base tables while the materialized view is being
>> refreshed, but with a denormalized schema, queries must be held up until
>> those hundreds or even thousands of rows are updated, assuming, of
>> that clients need the absolute latest values.
> You make some good points, but there's another one you
> didn't mention, and that is that manual denormalization is more
> error prone. You have to get it right everywhere you do an
> update, and that's not just in code. Also doing it manually
> means that every relevant programmer has to know the
> protocol, and follow it without mistake, every time, instead
> of just declaring the intent and letting the computer handle it.
You're absolutely right.
Received on Wed Mar 05 2008 - 21:02:36 CET