Re: SQL Statement Help Needed
От | Jaime Casanova |
---|---|
Тема | Re: SQL Statement Help Needed |
Дата | |
Msg-id | c2d9e70e0512061055m3b9a939aqf783b715148f3ad4@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: SQL Statement Help Needed (<me@alternize.com>) |
Список | pgsql-novice |
On 12/5/05, me@alternize.com <me@alternize.com> wrote: > From: <operationsengineer1@yahoo.com> > > the reason for doing this is that you eliminate > > database dead space (people that don't have faxes > > won't store a null in the db (i think it is null) and > > the db won't have to manage the null values). > > correct me if i'm wrong, but i don't think having a completely normalized > datastructure makes always sense. if one would need to query an employee and > having all phone numbers & stuff in one single view, you'll end up having a > huge amount of joins. this is bound to "cost" performance while the "win" > (diskspace) is relatively small. > > - thomas > there are cases, but you still want to justify yourself the use of denormalized data... -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)
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