Hibernate Search Seam

8/6/2019 Hibernate Search Seam

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Copyright Red Hat 2007-2009

Hibernate SearchGoogling your persistence domain model

Emmanuel BernardDoer

JBoss, a division of Red Hat

Monday, April 20, 2009


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Search: left overof todays applications

Add search dimension to the domain model

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Frankly, search sucks on this project

-- Anonymous boss

Why? How to fix that? For cheap?



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Integrate full-text search andpersistent domain

SQL Search vs Full-text Search

Object model / Full-text Search mismatches

Demo

Hibernate Search architecture

Configuration and Mapping

Full-text based object queriesSome more features

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SQL search limits

Wildcard / word search

%hibernate%

Approximation (or synonym)hybernat

Proximity

Java close to PersistenceRelevance or (result scoring)

multi-column search

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Full Text Search

Search information

by word

inverted indices (word frequency, position)

In RDBMS engines

portability (proprietary add-on on top of SQL)

flexibility

Standalone engine

Apache Lucene(tm) http://lucene.apache.org

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http://lucene.apache.org/http://lucene.apache.org/http://lucene.apache.org/


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Mismatches with a domain model

Structural mismatch

full text index are text only

no reference/association between documentSynchronization mismatch

keeping index and database up to date

Retrieval mismatch

the index does not store objects

certainly not managed objects

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ApplFwk

Persistence

Search

Domain

Model



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Copyright Red Hat 2007-2009 7

DemoLets google our application!



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Hibernate Search

Under the Hibernate platform

LGPL

Built on top of Hibernate CoreUse Apache Lucene(tm) under the hood

In top 10 downloaded at Apache

Very powerful but low leveleasy to use it the wrong way

Solve the mismatches

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ApplFwk

Persiste

nce

DomainModel

Search

JBoss Seam



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Architecture

Transparent indexing through event system (JPA)

PERSIST / UPDATE / DELETE

Convert the object structure into Index structure

Operation batching per transaction

better Lucene performance

ACID-ity

(pluggable scope)

Backend

synchronous / asynchronous mode

Lucene, JMS 9Monday, April 20, 2009


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Architecture (Backend)

Lucene Directory

standalone or symmetric cluster (limited scalability)

immediate visibility

can afect front end runtime

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Database

Lucene

Directory

(Index)

Hibernate+

Hibernate Search

Search request

Index update

Hibernate+

Hibernate Search

Search requestIndex update



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Architecture (Backend)

JMS (Cluster)

Search processed locally / Change sent to master

asynchronous indexing (delay)

No front end extra cost / good scalability

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DatabaseHibernate+

Hibernate Search

JMS

queue

Lucene

Directory

(Index)

Master

Hibernate+

Hibernate SearchProcessIndex update

Index update order

Lucene

Directory

(Index)

Copy

Search request

Copy

Slave

Master



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Configuration and Mapping

Configuration

event listener wiring

transparent in Hibernate AnnotationsBackend configuration

Mapping: annotation based

@Indexed

@Field(store, index)

@IndexedEmbedded

@FieldBridge 12Monday, April 20, 2009


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Query

Retrieve objects, not documents

no boilerplate conversion code!

Objects from the Persistence Context

same semantic as a JPA-QL or Criteria query

Use org.hibernate.Query/javax.persistence.Query

common API for all your queries

Query on correlated objects

JOIN-like query "author.address.city:Atlanta"

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Query possibilities

bring the best document first

recover from typos

recover from faulty orthography

find from words with the same meaning

find words from the same family

find an exact phrasefind similar documents

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More query features

Fine grained fetching strategy

Sort by property rather than relevance

Projection (both field and metadata)metadata: SCORE, ID, BOOST etc

no DB / Persistence Context access

Filterssecurity / temporal data / category

Total number of results

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Some more features

Automatic index optimization

Index sharding

Manual indexing and purging

non event-based system

Shared Lucene resources

Native Lucene access

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Full-Text search without thehassle

Transparent index synchronization

Automatic Structural conversion through Mapping

No paradigm shift when retrieving data

Clustering capability out of the box

Easier / transparent optimized Lucene use

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Road Map

Programmatic Mapping API Perf

Multi threaded mass index

Clustering

Query

Dictionary and spellchecker

Easier query buildingMoreLikeThis?

Statistics

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Q&A



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Hibernate Search

http://search.hibernate.org

Hibernate Search in ActionApache Lucene

http://lucene.apache.org

Lucene In Action

http://in.relation.to

http://blog.emmanuelbernard.com

For More Information

http://in.relation.to/http://in.relation.to/http://lucene.apache.org/http://blog.emmanuelbernard.com/http://blog.emmanuelbernard.com/http://in.relation.to/http://in.relation.to/http://lucene.apache.org/http://lucene.apache.org/http://www.hibernate.org/http://www.hibernate.org/

Hibernate Search Seam

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