Subject: Postgres and Textual data

From: [email-masked] (Vikas Aggarwal)
Date: Tue, 26 May 92 15:50:40 -0700

I was wanting to use postgres in a library cataloging system- essentially
all the fields (Title, Author, Description) will be textual data and
I will be performing 'textregexeq' kind of searches on the fields.

1. Any plans on using the Henry Spencer collection of regex routines instead
   of the system's C library version ? Henry Spencer's colleciton is much more
   flexible (and used in Perl, etc. also) and is perhaps faster than the
   library call.

2. How do I create indexes on the words of the various fields ? I am sorry
   but I am sketchy on the use of indexes on words and regular expressions.

Has anyone written their own procedure and data type for this kind of funciton
at all ? Any comments on this undertaking would be greatly appreciated. The
size of the data is about 100,000 records of text information (each with
the standard library fields).

Appreciate any and all feedback,,,

 -vikas
 [email-masked]						(609) 258-2403
 ...rutgers!jvncnet!vikas
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From: postarch (Postgres Mailing Archive)
Date: Thu, 28 May 92 09:26:17 PDT

>   flexible (and used in Perl, etc. also) and is perhaps faster than the

No, but Postgres is an exstensible system and you can add the functions and
operators that use whatever regular expression implementation you prefer.

>   but I am sketchy on the use of indexes on words and regular expressions.

btree indices are no good when it comes to regular expressions.  I'm not sure
a good indexing scheme exists for this.

Jeff Meredith
[email-masked]