Hibernate
description
Transcript of Hibernate
Hibernate
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Introduction
ORM goal: Take advantage of the things SQL databases do well, without leaving the Java language of objects and classes.
ORM real goal: Do less work and have a happy DBA.
Hibernate is an open-source ORM toolkit for the Java language, providing a framework for mapping an object-oriented domain model to a traditional relational database.
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Hibernate Architecture
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XML
XML (Extensible Markup Language) is a human readable way of describing structured data.
XML is made up of tags enclosing text:<dataset>
<record><name>David</name><age>47</age>
</record></dataset>
Mapping Java classes to database table is accomplished through the configuration of an XML file.
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SQL
SQL (Structured Query Language) is a standard language for accessing and manipulating relational databases.
SQL queries allow the user to specify a description of the desired result set:
SELECT title, price
FROM Book
WHERE price > 100.00
ORDER BY title
SQL is designed for the retrieval and management of data in database and database schema creation and modification.
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Hibernate query options
• Hibernate Query Language (HQL)• “minimal” object-oriented dialect of ANSI SQL
• Criteria Queries (QBC)• extensible framework for query objects• includes Query By Example (QBE)
• Native SQL queries• SQL queries may be defined and called exactly HQL
query
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Hibernate Features
• Persistence for POJOs (JavaBeans)
• Flexible and intuitive mapping
• Support for fine-grained object models
• Powerful, high performance queries
• Dual-Layer Caching Architecture (HDLCA)
• Lazy loading
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