ajayshah@alhena.usc.edu (Ajay Shah) (04/05/91)
Article 9209 of comp.databases:
From: tony@oha.UUCP (Tony Olekshy)
Subject: Opinions on C-Tree (from the C-Tree mailing list).
Date: 6 Feb 91 08:00:24 GMT
Organization: Olekshy Hoover & Associates Ltd., Edmonton, Alberta, Canada.
Hello. This is you friendly C-Tree mailing list maintainer. I too am very
pleased with the C-Tree ISAM manager. I have used it for a variety of
applications, and currently use it to store a `virtual schema' for accessing
multiple databases, and some other things they say I can't talk about.
C-Tree runs on almost anything, supports variable length records, a very fancy
B-Tree+ algorithm, multi-user locking, and an ISAM server that communicates
with application clients using IPC. I have used the server with various Unix
and with VMS (my DOS code runs single-user to date, although you get various
LAN code in the distribution). Note that this is not, apparently, the same
server stuff being discussed by other posters to this thread, or else the
posting about binary only servers is wrong--more later.
This server consideration is important, because the server can buffer data
in a mult-iuser environment that would otherwise have to be flushed in order
for stand-alone multi-user access to see a consistent database. We see a five
times improvement in bulk loads while running multi-user with the server over
stand-alone multi-user access.
There are tradeoffs here, because writing ISAM code in C is lower level than
using some fancy so-called SQL (warning, bias alert), but there is also the
very real consideration that I paid once for a reasonable source license, and
I can distribute binaries I compile from that source forever. If you're
popping out lots of low-priced product, this is critical. Last time I
checked (but don't quote me, please), the source license for C-Tree was
something like $400 *per* *programmer*, which I find to be an innovative but
particularly reasonable arrangement.
I do use R-Tree for repetitive reports (such as those on my DD itself), but
I have no experience with the other FairCom products.
The C-Tree mailing list is, as you might suspect, not associated with FairCom
in any way. There are currently ~70 subscribers. You can send mail for the
next digest to the address in my signature below, substituting ctree for tony.
Requests to be added to the list, and other administration mail, should
substitute ctree-request for tony. Opinions expressed in the ctree mailing
list are those of the authors of each piece of mail.
I'm sure the mailing list would like to know if, and where, I have erred in
this posting.
--
Yours etc., Tony Olekshy. Internet: tony%oha@CS.UAlberta.CA
BITNET: tony%oha.uucp@UALTAMTS.BITNET
uucp: alberta!oha!tony
Where the spirit does not work with the hand there is no art. --Da Vinci
--
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Ajay Shah, (213)734-3930, ajayshah@usc.edu
The more things change, the more they stay insane.
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