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From: oz@nexus.YorkU.CA (Ozan Yigit)
Newsgroups: comp.archives
Subject: [ultrix...] sdbm is available.
Keywords: dbm,ndbm,sdbm
Message-ID: <1990Dec15.220221.25375@ox.com>
Date: 15 Dec 90 22:02:21 GMT
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Archive-name: database/dbm/sdbm/1990-12-13
Archive: nexus.yorku.ca:/pub/oz/sdbm.shar.Z [130.63.9.1]
Original-posting-by: oz@nexus.YorkU.CA (Ozan Yigit)
Original-subject: sdbm is available.
Reposted-by: emv@ox.com (Edward Vielmetti)

A complete clone of Berkeley's ndbm, called sdbm is available.
It is currently ftp-able from nexus.yorku.ca [130.63.9.1] as
pub/oz/sdbm.shar.Z.

points of interest:

+ A complete functional clone of ndbm, using a fast and simple external
  hashing algorithm: "Dynamic Hashing" (1978) by P.-A. Larson.

+ sdbm is fully public domain. There is no pedantic, overbearing or
  infectious copyright/left to put up with. It is unconditionally yours,
  and everybody-else's. You can do whatever you like with it.

+ sdbm is faster and safer than ndbm, but shares the same shortcomings:
  limited size records, holes. On the other hand, ndbm needs no apologies:
  it has proven itself to be extremely useful within its limitations. The
  sdbm pagefiles are smaller than ndbm, and contain fewer holes.

+ sdbm has some additional flexibility due to a more generic database
  setup routine which allows you to use application-specific database
  naming conventions. It also allows the replacement of the hash function.

+ sdbm uses the same pagefile format ndbm uses, and the distribution comes
  with some rudimentary (read: hacky) tools and routines that can process
  these pagefiles. Even if you choose not to use sdbm, you can still take
  advantage of this additional information about pagefiles.

+ sdbm is *not* database compatible with ndbm. This is due to the hash
  functions used in ndbm and sdbm, and to the order in which the page
  addresses are generated.

+ sdbm provides enough infrastructure for you to be able to experiment
  with other algorithms, especially the so-called "directory-less"
  external hashing algorithms: linear hashing, spiral storage etc. The
  code is [I think] clean, easy to understand and compatible.

I look forward to comments, suggestions, improvements.

enjoy...        oz
---
[NOTE to all beta users: the copyright that accompanied the beta release
is now dropped. Also, this distribution contains an important bugfix due
to Liam R Quin of SoftQuad. Please contact me if you have no FTP access.]
---
Where the stream runneth smoothest,   | Internet: oz@nexus.yorku.ca
the water is deepest.  - John Lyly    | UUCP: utzoo/utai!yunexus!oz