Re: double linked list
Date: 9 Feb 2003 18:08:47 -0800
Message-ID: <c0d87ec0.0302091808.65d6bca5_at_posting.google.com>
>> [book on TREES & HIERARCHIES IN SQL] Are we rediscovering the past?
Actually, I spend most of the time showing how to code hierarchies
without using links, but by taking a set-oriented approach, like the
one I just did a "cut & paste" on.
Actually, the old network and IMS databases are really fast to load
and access. They just have no flexibility. It's like a Polar Bear --
great in one environment and no place else.
If you put parts subordinate to their suppliers, and want to get all
the sources for a "Metric #5 Machine Screw", you will be chasing
pointer chains from the supplier, thru his catalog, back to the next
supplier, thru his catalog, etc.
Network model databases have their place and can out perform a RDBMS
in those cases. It's just that those cases are few and far between. In
my experience, it's when the data is static, ie, load data once and
read many times very fast. Dynamic data just bogs done on link
updates. <<