Re: Relational vs network vs hierarchic databases
Date: Sat, 20 Nov 2004 14:19:12 -0700
Message-ID: <usm748bhr.fsf_at_mail.comcast.net>
an associated issue related to indexes ... I recently commented about in context of filesystem structures ... but it also applies to database structures.
a big driving factor in the 60s was the limited amount of real storage. with the increasing amount of real storage available by the late 70s, it became more realistic to cache index structures ... off-setting some of the performance penalty vis-a-vis direct pointers.
some number of the filesystem implementations even leveraged real storage to switch from disk-based paradigm to real-stroage based paradigm (with periodic checkpointing to disk) .... enabling various kinds of lighter weight allocation implementations (which would have been impractical when everything was strictly disk resident).
a couple filesystem trade-off posts
http://www.garlic.com/~lynn/2004o.html#0 CKD Disks?
http://www.garlic.com/~lynn/2004o.html#22 Integer types for 128-bit addressing
-- Anne & Lynn Wheeler | http://www.garlic.com/~lynn/Received on Sat Nov 20 2004 - 22:19:12 CET