Mailing-List: contact lucene-user-help@jakarta.apache.org; run by ezmlm
Precedence: bulk
Reply-To: "Lucene Users List" <lucene-user@jakarta.apache.org>
Content-Type: text/plain;
  charset="iso-8859-1"
From: Tatu Saloranta <tatu@hypermall.net>
Reply-To: tatu@hypermall.net
Organization: Linux-users missalie
To: "Lucene Users List" <lucene-user@jakarta.apache.org>
Subject: Re: Wildcard workaround
Date: Thu, 29 May 2003 18:57:57 -0600
User-Agent: KMail/1.4.3
References: <336674949053D511BF4D00A0C9B3D3649EAF0D@SONIA>
 <01e101c3250e$5ece8af0$6822a8c0@medined01>
In-Reply-To: <01e101c3250e$5ece8af0$6822a8c0@medined01>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Message-Id: <200305291857.57430.tatu@hypermall.net>

On Wednesday 28 May 2003 05:43, David Medinets wrote:
> ----- Original Message -----
> From: "Andrei Melis" <Andrei.Melis@snt.ro>
>
> > As far as I have understood, lucene does not allow search queries
> > starting with wildcards. I have a file database indexed by content
> > and also by filename. It would be nice if the user could perform a
> > usual search like "*.ext".
>
> Does anyone know if Oracle patented the technique that they use for *ext
> searching in the Oracle Text product. If not, I'm sure the technique can be
> borrowed.
>
> On the other hand, the slow technique of comparing each term to *.ext can
> certainly be implemented with a minimum of effort, I think.

[apologies if somebody else already pointed this out... I missed some mails to 
the list from yesterday]

One of the most interesting solutions somebody posted earlier, was to use
2 indexes; one for 'normal' searches, with normal analyzer etc, and second
one that uses reversed words; ie. analyzer reverses words tokenized by
standard analyzer. This second index would then allow for searches
to do prefix match, in this case query would be something like

reverse_field:txe.*

This would work efficiently, although pretty much double the size of index for 
content that has to be prefix-searchable. Still, this solution somehow 
appeals to my hacker side. :-)

In this specific case, though, what others have suggested (add file prefix as 
separate field to search on), is probably more practical.

-+ Tatu +-


---------------------------------------------------------------------
To unsubscribe, e-mail: lucene-user-unsubscribe@jakarta.apache.org
For additional commands, e-mail: lucene-user-help@jakarta.apache.org