lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Anshum <ansh...@gmail.com>
Subject Re: Querying wildcard
Date Thu, 30 Oct 2008 05:28:44 GMT
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
> >
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message