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From "Aditi Goyal" <aditigupt...@gmail.com>
Subject Re: Querying wildcard
Date Thu, 30 Oct 2008 06:43:11 GMT
Thanks Anshum and Eric.

Well, I was looking for something like searching by domain name in the email
address etc.
How can I reverse the tokens? Can you please explain in little detail?

Thanks,
Aditi

On Thu, Oct 30, 2008 at 10:58 AM, Anshum <anshumg@gmail.com> wrote:

> Hi Aditi,
> As Eric mentioned, we'd need to know more to provide a rather apt solution.
> At the same time, a prefix wildcard is a highly unoptimized thing for
> lucene
> because of the way the index is stored/read. Ideally you'd atleast want to
> reverse the tokens as already mentioned.
> This is because the index terms are lexically sorted while storing and so
> the seem/fetch is efficient under normal cases(and not under the case of a
> prefix wildcard).
>
> --
> Anshum Gupta
> Naukri Labs!
> http://ai-cafe.blogspot.com
>
> The facts expressed here belong to everybody, the opinions to me. The
> distinction is yours to draw............
>
>
> On Wed, Oct 29, 2008 at 6:04 PM, Erick Erickson <erickerickson@gmail.com
> >wrote:
>
> > Sure, there are many tricks. If you search the mail archives you'll
> > find a bunch of them.
> >
> > One would be to reverse the tokens and make your leading
> > wildcard queries into trailing ones on the reversed field.
> >
> > But without more details about what you're trying to accomplish,
> > there's not much really useful advice we can offer.
> >
> > Best
> > Erick
> >
> > On Wed, Oct 29, 2008 at 7:15 AM, Aditi Goyal <aditigupta20@gmail.com>
> > wrote:
> >
> > > Hi All,
> > >
> > > I have been wanting to do a wildcard search with * as a first letter on
> > an
> > > index.
> > > Is there a way out except for setAllowLeadingWildcard() of QueryParser
> to
> > > true? Because, i have heard it is an expensive operation.
> > >
> > > Thanks
> > > Aditi
> > >
> >
>

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