postgresql

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History

Tom Lane 65b6868b13 Replace ad-hoc insertions into pg_opclass and friends with CREATE OPERATOR CLASS commands. Further tweaking of documentation for same.		2002-07-30 17:34:37 +00:00
..
isbn_issn.c	New pgindent run with fixes suggested by Tom. Patch manually reviewed,	2001-11-05 17:46:40 +00:00
isbn_issn.sql.in	Replace ad-hoc insertions into pg_opclass and friends with CREATE	2002-07-30 17:34:37 +00:00
Makefile	To fix the perpetually broken makefiles in the contrib tree, I have	2001-09-06 10:49:30 +00:00
README.isbn_issn	Add missing /contrib files	2000-06-19 14:02:16 +00:00

README.isbn_issn

ISBN (books) and ISSN (serials)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This directory contains definitions for a couple of PostgreSQL
external types, for a couple of international-standard namespaces:
ISBN (books) and ISSN (serials).  Rather than just using a char()
member of the appropriate length, I wanted my database to include
the validity-checking that both these numbering systems were designed
to encompass.  A little bit of research revealed the formulae
for computing the check digits, and I also included some validity
constraints on the number of hyphens.

The internal representation of these types is intended to be
compatible with `char16', in the (perhaps vain) hope that
this will make it possible to create indices of these types
using char16_ops.

These are based on Tom Ivar Helbekkmo's IP address type definition,
from which I have copied the entire form of the implementation.

Garrett A. Wollman, August 1998