Hi,Emmanuel
i think you did a very greate job! Since i am now working on a system
that
using lucene to implement a search engine, i would like to know some more
details about Hinbernate Search.
I have read some of the code in Hinbernate 3.2GA release, the code is
pretty cool, but there is one thing i doubt:
For the update operation Hibernate Search used remove & update.which
refer
to Lucene's deleteDocuments method. That's ok and i also could only find
this way to update the index data. This will works fine when the operation
does not have high frequency.
But as i know the remove operation in lucene only marked a tag for the
deleted document without actually delete the data ofr index files. We
know
in some systems the data would be updated in a very high frequency(eg. an
traffic status query system), then it will not take a long time that the
index will be filled with lots of expired document data, even if the data
update is not as fast as a traffic status, i think this problem is still
very critical since things we stored in databases are always updating.
Is there any way to solve this in Hibernate Search?
Richie
2006/11/19, Emmanuel Bernard <[EMAIL PROTECTED]>:
>
> I forgot a couple of things.
> I do not think that all your object properties belongs to the Index, and
> some of them will be put in the index with information degradation (ie
> store year/month rather than the whole date). So I do not believe there
> is a bidirectional relationship between your domain model and your index
> documents (for size, efficiency and accuracy purpose).
> For that matter, Compass cannot really truly index your database backed
> domain model and give back the object to you. Hibernate Search can
> because it delegate the object hydration to Hibernate Core.
>
> Of course that's my opinions, and some people can disagree ;-)
>
> Emmanuel Bernard wrote:
> >
> > Hi,
> > I am not really familiar with Compass I haven't really looked at the
> > code, Hibernate Lucene (now renamed Hibernate Search) started from a
> > user demand. I had some in depth discussions though, with some users
> > that evaluated both Compass and Hibernate Search that helped me drive
> > its design.
> >
> > Here are the arguments in favor of Hibernate Search:
> > 1. not Yet Another API to deal with your domain model
> > If you already use an ORM (JPA or Hibernate), you are familiar with
> > those APIs. Using compass implies that you have to use a different set
> > of API to play with the object lifecycle (CRUD).
> > Hibernate Search is integrated with the org.hibernate.Query interface,
> > and all the CUD operations on the index are triggered from the
Hibernate
> > CUD operations.
> >
> > 2. Metadata
> > Metadata are minimal and fit particularly well through annotations, so
> > you don't have yet another XML representation of ther same domain
model
> > (Compass might now have annotations support, you'll have to check)
> >
> > 3. it's all about managed objects (ie managed by the Session or the
> > EntityManager)
> > Hibernate Search gives you back objects managed by the Session, so any
> > change made to them will (by default) be synchronized with the
database,
> > this is the normal behavior of an ORM, but is not what you have from a
> > Compass search.
> > This approach fits well with the JBoss Seam approach of having all the
> > application around the domain model and EJB 3.0
> >
> > 4. Not too much abstraction
> > From what I've heard, Compass borrow a lot of its design / classnames
> > from Hibernate/Spring/Lucene. Compass tries to abstract those 3
> > techlnologies (at least Hibernate and Lucene), by providing its own
> > infrastructure.
> > What am trying to do with Hibernate Search is to keep the
abstraction as
> > light as possible. For advanced Lucene query you'll have to use pure
> > Lucene APIs, which is possible / natural with Hibernate Search
> >
> >
> > I invite you to check these links (which I expect to release soon)
> >
>
http://www.mail-archive.com/hibernate-dev%40lists.jboss.org/msg00392.html
> > and for the future (but flexible)
> >
>
http://www.mail-archive.com/hibernate-dev%40lists.jboss.org/msg00393.html
> >
> > HTH
> >
> > Emmanuel
> >
> > Lukas Vlcek wrote:
> > >
> > > Emanuael,
> > > I would be glad to hear your answer here (on user list).
> > > Regards,
> > > Lukas
> > >
> > > ---------- Forwarded message ----------
> > > From: Emmanuel Bernard <[EMAIL PROTECTED]>
> > > Date: Nov 13, 2006 11:07 PM
> > > Subject: Re: Hibernate Lucene trademark issues
> > > To: java-dev@lucene.apache.org, [EMAIL PROTECTED]
> > >
> > > Hi Lukas,
> > > I'd be happy to answer your question, but I don't think Lucene
dev is
> > > the appropriate area for that kind of discussion.
> > > let's move this discussion here
> > > http://forum.hibernate.org/viewforum.php?f=9 (or in the Lucene User
> list
> > > if you want to).
> > >
> > > Emmanuel
> > >
> > > Lukas Vlcek wrote:
> > > >
> > > > Hi Emmanuel,
> > > >
> > > > I am interested in you solution. I have a plan to use lucene and
> > > hibernate
> > > > in my next project and search will play very important role
> > > > (*stake-holder*
> > > > functionality). I have heard of
> > > > comapss<http://www.opensymphony.com/compass/>project which
> introduces
> > > > searching (lucene) layer on top of hibernate also.
> > > > I haven't had a change to study it in detail yet.
> > > >
> > > > Do you think you could give me some high level comments about your
> > > > motivation for implementing lucene search directly in hibernate
> code,
> > > > couldn't you just use compass project? Is there any fundamental
> > > difference
> > > > between your approach and comapss?
> > > >
> > > > Many thanks,
> > > > Lukas
> > > >
> > > > On 11/6/06, Emmanuel Bernard <[EMAIL PROTECTED]> wrote:
> > > > >
> > > > > Hi guys,
> > > > > I'm Emmanuel Bernard from JBoss.
> > > > > I'm the current lead developer of the Hibernate Lucene
integration
> > > > module.
> > > > > The goal of this project is to facilitate the integration of a
> > search
> > > > > capability to Hibernate based applications. And guess what,
I use
> > > Lucene
> > > > > ;-)
> > > > >
> > > > >
> > > >
> > >
> >
>
http://www.hibernate.org/hib_docs/annotations/reference/en/html/lucene.html
> > > > >
> > > >
> > >
> >
>
http://www.mail-archive.com/hibernate-dev%40lists.jboss.org/msg00392.html
> > > > >
> > > > > I realized this week end that the 'Hibernate Lucene' name might
> > > infringe
> > > > > the Apache Lucene trademark policy.
> > > > > http://www.cafepress.com/lucene/ seems to state that Lucene is a
> > > > > trademark of the Apache Software Foundation (nice golf shirt
BTW)
> > > > > But I wasn't able to find any document explaining the fair use
> > of the
> > > > > Lucene brand (the license as well as the notice seem to be
silent
> on
> > > > > this subject).
> > > > >
> > > > > Even if Lucene in not trademarked, what do you consider a fair
> > use of
> > > > > your brand? I'm happy to rename my project, I guess the initial
> > choice
> > > > > was more a tribute to your project than anything else.
> > > > >
> > > > > Emmanuel
> > > > >
> > > > > PS: please forward this email to the appropriate persons if this
> > > is not
> > > > > the case already (PMC or whatever)
> > > > >
> > > > >
> > > > >
> > ---------------------------------------------------------------------
> > > > > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > > > > For additional commands, e-mail: [EMAIL PROTECTED]
> > > > >
> > > > >
> > > >
> > >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: [EMAIL PROTECTED]
> > For additional commands, e-mail: [EMAIL PROTECTED]
> >
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
>
>
