CSC/ECE 517 Fall 2007/wiki2 2 aa

Object-relational mapping. Ruby's ActiveRecord is one attempt to allow an object-oriented program to use a relational database. The Crossing Chasms pattern is another. Look up several approaches to mapping relational databases to o-o programs, include hyperlinks to all of them, and explain how they differ. Report on the strengths of various approaches (making sure to credit the authors for their insights).

Introduction

Object-oriented programming uses Object to manage data. Objects have identity, state, and behavior, which means Object is focus on identity and behavior of the things in real world.

Object-relational Mapping

Object-relational mapping is a programming technique or process to transform data between relational database and a set of objects in object-oriented programming.

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Comparison

In Hibernate, you'd usually begin development by working on your Java objects because Hibernate is a mapping framework. The object model becomes the center of your Hibernate universe. Active Record is a wrapping framework, so you start by creating a database table. The relational schema is the center of your Active Record universe. Active Record also includes some features that many Java frameworks don't have, such as model-based validation.Model-based validation lets you make sure the data within your database stays consistent.

Reference

1. Wikipedia Definition
2. Object Modeling
3. ORM Thesis[1]
4. Crossing borders: Exploring Active Record

External Links

1. O/R Mapping Products

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