Re: Quote from comp.object
Date: 28 Feb 2007 10:25:44 -0800
Message-ID: <1172687144.818888.55610_at_s48g2000cws.googlegroups.com>
On Feb 28, 11:43 am, "Aloha Kakuikanu" <aloha.kakuik..._at_yahoo.com>
wrote:
> On Feb 28, 5:48 am, "-CELKO-" <jcelko..._at_earthlink.net> wrote:
>
> > I think he missed the point of RDBMS versus hierarchical databases.
>
> > Yes, a hierarchical database like IMS (which has more data in it than
> > all the SQL enterprise products combined) devoted to one job will run
> > really fast. You tune for that one job. But it will not handle any
> > other jobs very well.
>
> And not so much faster to be really concerned. Consider:
>
> 1. Extracting a set of records from a single table by some criteria.
> There has to be a B-tree walk in both cases. Performance is the same.
> 2. Extracting all children of a parent record by foreign key index
> versus extracting children by direct references. Logarithmic cost
> versus constant which is also not a big deal.