hi,
I guess it doesn't work without any iteration.
Another option coming to my mind: If the list of possible classnames isn't too
long, you could do (pseudocode)
Hashtable resultCount = new Hashtable();
foreach( string classname in possibleClassNames )
{
resultlist = index.SearchFor("Name:Menaria AND Class:"+classname)
resultCount[classname] = resultlist.Count;
}
cheers,
Erich
> -----Original Message-----
> From: Michael Mitiaguin [mailto:[EMAIL PROTECTED]
> Sent: Wednesday, May 30, 2007 9:33 AM
> To: [email protected]
> Subject: Re: Get all unique values of specific field
>
> Laxmilal ,
>
> What's the problem with a hit list iteration ( it should be
> very fast ) ?
> I am not sure about equivalent of SQL "distinct" in Lucene.
> You didn't describe whether you index ( and plus store ) all fields.
> Effectively you may just store a primary key ( let's say
> incremental int id for the sake of example , though you
> table doesn't look normalised , it doesn't really matter in
> our case ) which will be stored not indexed , the rest
> may be indexed as ( Name + Address + Class ...) or as
> separate fields if you need to and either stored or not stored.
> Having applied search "Name:Menaria" ( and having written
> all this I realised that you still need to iterate a hit list
> but let me finish
> :) ) you may form a string with coma delimited IDs and then
>
> "select distinct class from mytable where where id in "(" +
> formedstring + ") "
>
> Surely if you store everything in Lucene index , there is no
> need to query database and you may use collections for
> picking up distinct "Class" values , but my understanding
> you still need to iterate through Hits
>
> Regards
> Michael
>
> On 5/30/07, Laxmilal Menaria <[EMAIL PROTECTED]> wrote:
> > Hello everyone,
> >
> > I have created a Lucene Index of Students Database, this
> database have
> > 5 fields i.e. Name, Address, Class, PhoneNo and ScholarNo.
> > Now I have opened Searcher and query "Name:Menaria" , Its
> return 100
> > results. Now I wants the All unique "Class" names which is
> return in
> > Hits objects, How can I get unique Class list without using Loop.
> >
> > Please suggest me..
> >
> > --
> > Thanks,
> > Laxmilal menaria
> >
> > http://www.minalyzer.com/
> > http://www.chambal.com/
> >
>
