Fundamentals of object databases object oriented and object relational design pdf
File Name: fundamentals of object databases object oriented and object relational design .zip
- What Are Object-Oriented Databases And Their Advantages
- What is a Database Model
- [PDF Download] [(Fundamentals of Object Databases: Object-Oriented and Object-Relational Design
What Are Object-Oriented Databases And Their Advantages, are commonly used in applications that require high performance, calculations, and faster results.
What Are Object-Oriented Databases And Their Advantages
This creates, in effect, a "virtual object database " that can be used from within the programming language. There are both free and commercial packages available that perform object-relational mapping, although some programmers opt to construct their own ORM tools. In object-oriented programming , data-management tasks act on objects that are almost always non- scalar values. For example, consider an address book entry that represents a single person along with zero or more phone numbers and zero or more addresses.
The list of phone numbers would itself contain "PhoneNumber objects" and so on. Each such address-book entry is treated as a single object by the programming language it can be referenced by a single variable containing a pointer to the object, for instance. Various methods can be associated with the object, such as methods to return the preferred phone number, the home address, and so on.
By contrast, many popular database products such as SQL database management systems DBMS are not object-oriented and can only store and manipulate scalar values such as integers and strings organized within tables.
The programmer must either convert the object values into groups of simpler values for storage in the database and convert them back upon retrieval , or only use simple scalar values within the program.
Object-relational mapping implements the first approach. The heart of the problem involves translating the logical representation of the objects into an atomized form that is capable of being stored in the database while preserving the properties of the objects and their relationships so that they can be reloaded as objects when needed.
If this storage and retrieval functionality is implemented, the objects are said to be persistent. Implementation-specific details of storage drivers are generally wrapped in an API in the programming language in use, exposing methods to interact with the storage medium in a way which is simpler and more in line with the paradigms of surrounding code.
The following is a simple example, written in C code, to execute a query written in SQL using a database engine. In contrast, the following makes use of an ORM-job API, allowing the writing of code which naturally makes use of the features of the language. The case above makes use of an object representing the storage repository and methods of that object. Other frameworks might provide code as static methods, as in the below, and yet other methods may not implement an object-oriented system at all.
Often the choice of paradigm is made to fit the ORM best into the surrounding language's design principles. Usually, the framework will expose some filtering and querying functionality, allowing subsets of the storage base to be accessed and modified. The code below queries for people in the database whose ID value is '10'.
Compared to traditional techniques of exchange between an object-oriented language and a relational database, ORM often reduces the amount of code that needs to be written. Disadvantages of ORM tools generally stem from the high level of abstraction obscuring what is actually happening in the implementation code. Also, heavy reliance on ORM software has been cited as a major factor in producing poorly designed databases.
Another approach is to use an object-oriented database management system OODBMS or document-oriented databases such as native XML databases that provide more flexibility in data modeling. Document-oriented databases also prevent the user from having to "shred" objects into table rows.
Many of these systems also support the XQuery query language to retrieve datasets. Object-oriented databases tend to be used in complex, niche applications. One of the arguments against using an OODBMS is that it may not be able to execute ad-hoc, application-independent queries. A variety of difficulties arise when considering how to match an object system to a relational database. These difficulties are referred to as the object-relational impedance mismatch.
An alternative to implementing ORM is use of the native procedural languages provided with every major database. These can be called from the client using SQL statements. The Data Access Object DAO design pattern is used to abstract these statements and offer a lightweight object-oriented interface to the rest of the application. From Wikipedia, the free encyclopedia. Not to be confused with Object-role modeling. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources.
Unsourced material may be challenged and removed. FromSqlRaw sql. GetFirstName ;. Get 10 ;. Get Person. Hibernate Overview. Retrieved 19 April Retrieved 23 August CS1 maint: location link.
Data definition Data manipulation Query information retrieval. Activity monitoring Audit Forensics Negative database. Abstraction layer Object-relational mapping. Virtualization Tuning caching Migration Preservation Integrity.
Book Category WikiProject. Categories : Object-relational mapping Data mapping. Hidden categories: CS1 maint: location Articles needing additional references from May All articles needing additional references All articles with unsourced statements Articles with unsourced statements from September Articles with unsourced statements from September Use dmy dates from June Namespaces Article Talk.
Views Read Edit View history. Help Learn to edit Community portal Recent changes Upload file. Download as PDF Printable version.
What is a Database Model
Object-oriented database design is not only a simple extension of relational database design. By modeling structure as well as behavior of real-world entities as coherent units, object-oriented database design succeeds in capturing more semantics of applications already in the design phase. The use of objectoriented concepts like inheritance promises a more adequate modeling and a better application implementation based on an object-oriented database system. However, the results of object-oriented design can also be applied to classical database systems. In this paper we briefly compare object-oriented database design with traditional design of relational databases.
In this paper we briefly compare object-oriented database design with tra- ditional design of relational databases. It is not our intention to end up with stating that.
[PDF Download] [(Fundamentals of Object Databases: Object-Oriented and Object-Relational Design
In this article, you will learn what object-oriented databases are what are their advantages. The data is represented and stored in the form of objects. A database is a data storage.
Embed Size px x x x x All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted inany form or by any meanselectronic, mechanical, photocopy, recording, or any other except for brief quotations inprinted reviews, without the prior permission of the publisher. Lecture 12Series Editor: M.
This creates, in effect, a "virtual object database " that can be used from within the programming language. There are both free and commercial packages available that perform object-relational mapping, although some programmers opt to construct their own ORM tools. In object-oriented programming , data-management tasks act on objects that are almost always non- scalar values. For example, consider an address book entry that represents a single person along with zero or more phone numbers and zero or more addresses. The list of phone numbers would itself contain "PhoneNumber objects" and so on.