What is ORM?
ORM stands for Object-Relational Mapping (ORM) is a programming technique for converting data between relational databases and object oriented programming languages such as Java, C# etc. An ORM system has following advantages over plain JDBC
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S.N.
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Advantages
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1
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Lets business code access objects rather than DB tables.
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2
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Hides details of SQL queries from OO logic.
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3
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Based on JDBC 'under the hood'
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4
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No need to deal with the database implementation.
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5
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Entities based on business concepts rather than database structure.
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6
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Transaction management and automatic key generation.
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7
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Fast development of application.
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An ORM
solution consists of the following four entities:
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S.N.
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Solutions
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1
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An API
to perform basic CRUD operations on objects of persistent classes.
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2
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A
language or API to specify queries that refer to classes and properties of
classes.
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3
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A
configurable facility for specifying mapping metadata.
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4
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A
technique to interact with transactional objects to perform dirty checking,
lazy association fetching, and other optimization functions.
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