[Info-vax] Looking for some text search ideas

[Craig A. Berry]

On 9/26/14, 12:27 PM, David Froble wrote:

> Our applications are not using a RDBMS.

> A request has come up to be able to find any data which contains some
> specific text.  An example might be any product description that
> contains the text "gasket".  Using keys won't help, because the key
> might be "head gasket".

I assume from the talk of keys that these are RMS indexed files? Does
either the target of a search or the unit to be returned when you find
something ever span record boundaries, e.g.:

XYZ001This is a news-
XYZ002worthy message.

If I search for "newsworthy" should I consider that group of records a
match and return both records? Should I be able to match a word broken
across record boundaries? Are all the searches "word" searches with
clearly defined delimiters and known character sets? Or if I search for
"sage" should I match "message"?

I see from a subsequent post that you are just doing INSTR on arrays of
strings. If that works for you, that's fine. A good regular expression
engine would run circles around INSTR in both functionality and
performance. A full text search engine would too, and if the data are
simple, you could build your own with only moderate trouble that indexed
words (or characters if you wish) and saved either unique key values or
RFAs to get from the search string back to the containing record(s).