Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!mit-eddie!ll-xn!ames!oliveb!sun!hanami!landman
From: landman%hanami@Sun.COM (Howard A. Landman)
Newsgroups: comp.sys.mac.hypercard
Subject: Re: Large Scale DataBase
Message-ID: <69189@sun.uucp>
Date: 20 Sep 88 20:00:08 GMT
References: <52305GFX@PSUVM>
Sender: news@sun.uucp
Reply-To: landman@sun.UUCP (Howard A. Landman)
Organization: Sun Microsystems, Mountain View
Lines: 48

In article <52305GFX@PSUVM> GFX@PSUVM.BITNET writes:
>We use a rather large database (500,000 + records) holding  a few
>variables ( 25 +/-) related to industrial establishments.  We manage
>it with SAS on an IBM mainframe, but are curious as to whether such
>a dataBase could be installed in an HyperCard environment to provide
>interactive queries (a rarity, but nonetheless...)

>I would be delighted to hear from anyone with similar experience, or
>from anyone able to formulate educated guesses...

A really rough guess, based on my stack with 1,600 cards which takes
nearly .5 MB, would be: (500,000 / 1,600) * .5 MB, or about 156 MB.

>What we would have in mind at this time would be a single field per
>record, concatenating all the relevant information in less than, say,
>250 characters.  Basic questions are: what stack size would it mean?

An easy lower bound is 500,000 cards * 250 bytes/card = 125 MB; and that's
just for the text itself.  So the 156 MB above looks pretty reasonable.
Of course, if the average utilization of the field is much less than
250 chars, then it could be smaller.

>Is CD-ROM an alternative we should consider?

Not if you update things often, since you'd have to remaster the CD each time.
Plus, a CD-ROM drive will cost about the same as a large hard disk.

>Can we build the stack automatically from an ASCII file?

Building a text stack from an ASCII file is fairly straightforward.  I do
it in my Go Games and Fuseki stack.  Let me know if you want a copy ...

>What would be the expected search time?

The search speed of HyperCard gets slower as the size of the stack
increases, and if we assume linear degradation your searches might
take 2.5 hours since mine take up to half a minute.  (Additional searches
on the same key are much faster - I think HyperCard either builds indices
or at least scans ahead to the next one while you're not looking.)

>Any other approach you think is superior?

You should try to determine numbers for a fast database system (FoxBase?),
so you have a point of comparison.

	Howard A. Landman
	landman@hanami.sun.com
	UUCP: sun!hanami!landman