lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Erick Erickson" <erickerick...@gmail.com>
Subject Re: How to avoid duplicate records in lucene
Date Wed, 23 Jul 2008 13:40:28 GMT
Well, yes, that's expected behavior. Lucene makes no attempt to filter
"substantially similar" documents. From Lucene's perspective, you added
it twice, you must have had a good reason.

And no, it doesn't really display the same document twice. There are two
documents in Lucene that happen to have identical content. They'd
have different internal document IDs.

So what problem are you really trying to solve? Or are you just trying to
understand Lucene?

If you require that identical (or similar) documents are indexed only once,
you have to insure that yourself. Lucene is an *engine*, not a full-blown
application. So the various kinds of business logic restrictions are up
to you to implement.

Best
Erick

On Wed, Jul 23, 2008 at 12:36 AM, Sebastin <sebasmtech@gmail.com> wrote:

>
> Erick,
>
> example,
>
> IndexWriter writer = new IndexWriter("C:/index",new
> StandardAnalyzer(),true);
>
> String records = "Lucene" +" " +"action"+" "+"book" ;
>
> Document doc = new Document();
>
> doc.add(new
> Field("contents",records,Field.Store.YES,Field.Index.TOKENIZED));
>
>
> writer.addDocument(doc);
> writer.optimize();
> writer.close();
>
>
> when the records is inserted twice,while querying for "Lucene" it will
> display the same record twice.
>
>
>
>
>
>
>
>
> mark harwood wrote:
> >
> >>>Well, the point of my question was to insure that we were all using
> common terms.
> >
> > Sorry, Erick. I thought your "define duplicate" question was asking me
> > about DuplicateFilter's concept of duplicates rather than asking the
> > original poster about his notion of what a duplicate document meant to
> > him. You're right it would be useful to understand more about the
> > intention of the original message.
> >
> > Cheers
> > Mark
> >
> >
> >
> >
> >
> > ----- Original Message ----
> > From: Erick Erickson <erickerickson@gmail.com>
> > To: java-user@lucene.apache.org
> > Sent: Tuesday, 22 July, 2008 2:37:50 PM
> > Subject: Re: How to avoid duplicate records in lucene
> >
> > Well, the point of my question was to insure that we were all using
> common
> > terms. For all we know, the original questioner considered "duplicate"
> > records ones that had identical, or even similar text. Nothing in the
> > original question indicated any de-dup happening.
> >
> > I've often found that assumptions that we are all talking about the same
> > thing are...er...incorrect. And I don't want to waste my time answering
> > questions that weren't what was asked......
> >
> > Best
> > Erick
> >
> > On Mon, Jul 21, 2008 at 2:44 PM, markharw00d <markharw00d@yahoo.co.uk>
> > wrote:
> >
> >> >>could you define duplicate?
> >>
> >> That's your choice of field that you want to de-dup on.
> >> That could be a field such as "DatabasePrimaryKey" or perhaps a field
> >> containing an MD5 hash of document content.
> >> The DuplicateFilter ensures only one document can exist in results for
> >> each
> >> unique value for the choice of field.
> >>
> >> Cheers
> >> Mark
> >>
> >> Erick Erickson wrote:
> >>
> >>> could you define duplicate? As far as I know, you don't
> >>> get the same (internal) doc id back more than once, so what
> >>> is a duplicate?
> >>>
> >>> Best
> >>> Erick
> >>>
> >>> On Mon, Jul 21, 2008 at 9:40 AM, Sebastin <sebasmtech@gmail.com>
> wrote:
> >>>
> >>>
> >>>
> >>>> at the time search , while querying the data
> >>>> markrmiller wrote:
> >>>>
> >>>>
> >>>>> Sebastin wrote:
> >>>>>
> >>>>>
> >>>>>> Hi All,
> >>>>>>
> >>>>>> Is there any possibility to avoid duplicate records in lucene
>  2.3.1?
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>> I don't believe that there is a very high performance way to do
this.
> >>>>> You are basically going to have to query the index for an id before
> >>>>> adding a new doc. The best way I can think of off the top of my
head
> >>>>> is
> >>>>> to batch - first check that ids in the batch are unique, then check
> >>>>> all
> >>>>> ids in the batch against the IndexReader, then add the ones that
are
> >>>>> not
> >>>>> dupes. Of course all of your docs would have to be added through
this
> >>>>> single choke point so that you knew other threads had not added
that
> >>>>> id
> >>>>> after the first thread had looked but before it added the doc.
> >>>>>
> >>>>> I think Mark H has you covered if getting the dupes out after are
> >>>>> okay.
> >>>>>
> >>>>> - Mark
> >>>>>
> >>>>> ---------------------------------------------------------------------
> >>>>> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> >>>>> For additional commands, e-mail: java-user-help@lucene.apache.org
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>> --
> >>>> View this message in context:
> >>>>
> >>>>
> http://www.nabble.com/How-to-avoid-duplicate-records-in-lucene-tp18543588p18568862.html
> >>>> Sent from the Lucene - Java Users mailing list archive at Nabble.com.
> >>>>
> >>>>
> >>>> ---------------------------------------------------------------------
> >>>> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> >>>> For additional commands, e-mail: java-user-help@lucene.apache.org
> >>>>
> >>>>
> >>>>
> >>>>
> >>>
> >>>
> >>>
> ------------------------------------------------------------------------
> >>>
> >>> No virus found in this incoming message.
> >>> Checked by AVG. Version: 7.5.526 / Virus Database: 270.5.3/1563 -
> >>> Release
> >>> Date: 20/07/2008 12:59
> >>>
> >>>
> >>
> >>
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> >> For additional commands, e-mail: java-user-help@lucene.apache.org
> >>
> >>
> >
> >
> >
> >       __________________________________________________________
> > Not happy with your email address?.
> > Get the one you really want - millions of new email addresses available
> > now at Yahoo! http://uk.docs.yahoo.com/ymail/new.html
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> > For additional commands, e-mail: java-user-help@lucene.apache.org
> >
> >
> >
>
> --
> View this message in context:
> http://www.nabble.com/How-to-avoid-duplicate-records-in-lucene-tp18543588p18603752.html
> Sent from the Lucene - Java Users mailing list archive at Nabble.com.
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> For additional commands, e-mail: java-user-help@lucene.apache.org
>
>

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