Re: Use of regular expression

I should also mention that if you're on v5r4, you do get the normal
70-day trial period with 5722-DE1.

So you could install it and play it some.

Lastly, a caveat for both 5722-DE1 and OmniFind is that they may not
play well with your CMS. Here's a message in the archives from me
with more details....
http://archive.midrange.com/midrange-l/201007/msg00304.html

I don't believe the issues are show stoppers, I can think of a couple
of ways to work-around them. And IBM is supposed to be talking to one
of the CMS vendors to see what the options are.

Charles



On Mon, Jul 19, 2010 at 8:39 AM, Charles Wilt <charles.wilt@xxxxxxxxx> wrote:

Rick,

neither Reg-ex or standard SQL are going to give you decent
performance....as either way 1 billion records would have to be read.
I do agree with Jon that SQL should have the edge.

Your best option, if at 6.1 or 7.1, is the OmniFind text search
product; which is a no-charge option at those releases.
http://www-304.ibm.com/partnerworld/wps/servlet/ContentHandler/whitepaper/i/omnifind/search
http://publib.boulder.ibm.com/infocenter/iseries/v6r1m0/topic/rzash/rzash.pdf

If you're on v5r4 (or earlier), OmniFind's predecessor is the
chargeable 5722-DE1 Text Extender product.
http://publib.boulder.ibm.com/infocenter/iseries/v5r4/topic/books/sh126720.pdf

Lastly, OmniFind and Text Extender work by building special indexes.
You could conceivably roll your own version....but I'd be willing to
bet you'd wish you'd have just bought the software! :)


Charles




On Fri, Jul 16, 2010 at 5:06 PM,  <Rick.Chevalier@xxxxxxxxxxxxxxx> wrote:

I'm wondering if using regular expressions is a good way to handle a word search.  What I need is an exact match of a series of characters, say 'rick', in a character field.  I have only used regular expressions a couple of times and the syntax still gets me confused.  I think I see a way to do this with with something like r{1}i{1}c{1}k{1}.

I know I can do this with the %SCAN op code.  The reason I'm thinking about using regular expressions is the search will be over a table of close to 1 billion records and I'm looking for efficiencies any place I can find them.  If an expression can be created I want to do some comparisons between using a regular expression and %SCAN to see which is really the best performer.

Any thought would be appreciated.

Rick Chevalier
IT Software Solutions - Loan Servicing

________________________________
Privileged and Confidential. This e-mail, and any attachments there to, is intended only for use by the addressee(s) named herein and may contain privileged or confidential information. If you have received this e-mail in error, please notify me immediately by a return e-mail and delete this e-mail. You are hereby notified that any dissemination, distribution or copying of this e-mail and/or any attachments thereto, is strictly prohibited.
--
This is the RPG programming on the IBM i / System i (RPG400-L) mailing list
To post a message email: RPG400-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
or email: RPG400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/rpg400-l.