What Is Rdbms Ordbms And Oodbms Information Technology Essay
A set of computer programs which controls the formation, preservation, and the use of database with computer as a platform is called a database management system (DBMS). The control of organization-wide database development in the hands of database administrators (DBAs) is permitted by the database management system. It helps the use of integrated collection of data and files and also easily permits the access of the same database to different user application programs. The database models like network model or relational model can be used by the DBMS. Another feature of the DBMS is allows users and other software to store and get back data in a structured way in large systems. The users can write simple question in query language to retrieve information instead of writing computer programs. Fourth-generation programming language (4GLs) and other application development features provided by DBMS are very helpful to specify the logical organization for database and access and use the information within a database.
Relational Data Base Management System (RDBMS)
The abbreviation form of Relational Data Base Management System is RDBMS. The structure of RDBMS is database tables, fields and records. Each RDBMS table consists of database table rows and each database table row consists of one or more database table fields. RDBMS is used by main frame, midrange and microcomputers. MS SQL Server, DB2, Oracle and MySQL are the most popular RDBMS.
The data are stored in the form of tables which might be related by common fields. The data stored in the database table are manipulated by the rational operators given by RDBMS. SQL is the database query language in most RDBMS.
We will use the terms tables and relations interchangeably.
– In a RDBMS, the data is logically perceived as tables.
_ Tables are in logical data structures that we assume hold the data that the database intends to represents
_ And tables are not physical structures.
_ Each table have a unique table name
There are advantages and as well as disadvantages in the RDBMS. The advantages of RDBMS are
Fast and easy to pop out data as relation among entities is well defined
More secure and normalization
Problems are avoided when two things are processed at the same time
data can be managed in proper manner
The disadvantages on the other hand are
A professional is needed to deal with
Proper training is required
Need software and hard ware
The model is not easy to the end user to run quires
Object Relational Database Management System (ORDBMS)
The object relational database management system is known as a database management system which is alike to a relational database, but with an object oriented database model. This system supports classes, objects and inheritance directly in database schemas and in the query language. Besides, extension of the data model with custom data type and methods are supported by ORDBMS. The well-organized management from a limited set of data types is focused in traditional RDBMS but object relational DBMS on the other hand permits web sites development experts to join their own data types and methods.
Advantages of ORDBMS:
Large storage capacity is ensured in Object Relational Database Management Systems which benefits for the web based development.
Reasonably quick access speed
Massive scalability of ORDBMS is beneficial.
Outstanding manipulation power of object databases is boasted in ORDBMS
APIs and server subsystems are added to support object functionality.
The database engine is completely redesigned
A new object-oriented layer is added to support rich data types
Disadvantages of ORDBMS
ORDMBS fails in High speed internet applications.
The IDC opines that the ORDBMS market has the possibility to exceed the size of ODBMS in the next two years time in web based development
Object Oriented Database Management system (OODBMS)
Object Oriented Database Management system is the most excellent alternative to resolve impedance mismatch causing in the use of Relational Database Management System as objects have to be mapped to table. Database management is combined with object oriented programming concepts by the object oriented database management system. The principles of database management such as isolation, durability, consistency and atomicity and the object oriented programming concepts consist of of inheritance, encapsulation and polymorphism. The mixture of these ideas permits easiness in the management of large number of data, results in system reliability and guarantees support for query languages.
Therefore, from the description given above it can be concluded that an OODBMS is not only a database management system but also a complete object oriented development setting. Software development companies use OODBMS as an alternative because it follows intelligibility while objects are accessed in the database.
The Main objective of the OODBMS is to give consistent, data independent, secure, controlled and extensible data management services to support the object-oriented model. They were created to handle big and complex data that relational databases could not.
The most main characteristic is the joining of object-oriented programming with database technology, which provides an integrated application development system. Object-oriented programming results in 4 main characteristics: inheritances, data encapsulation, object identity, and polymorphism.
Object Identity, Object Structure, and Type Constructors
An OO database system provides a unique identity to each independent object stored in the database. This unique identity is typically implemented via a unique, system-generated object identifier (OID). The OID cab is assigned to program variables of the appropriate type when needed.
The main property required of an OID is that it be immutable; that is, the OID value of a particular object should not change. This preserves the identity of the real-world object being represented.
Merits of OODBMS over RDBMS
The impedance mismatch is completely cancelled out in OODBMS and on the other hand in a relational database system a problem is always faced by a custom software development company. There was lot of wastage of time in RDBMS while objects had to be mapped with tables and the table mapped with objects.
In the RDBMS, problems have to be faced by the users when identifying the records and they have to make sure that no two records have the same primary key. In the OODBMS this problem is completely avoided by its unique OIDs.
OODBMS can deal with complex data than RDBMS as in ODBMS, a large class able to hold lot of intermediate sized classes, which can keep even more medium sized classes.
The database management system maintains the connection between objects and the constraints on objects in an object oriented database, which means, the objects themselves. They permit support of complex application which is not supported by the other models. The programmability and performance, improve navigational access, and simplify concurrency control are improved by the object oriented database. The risks linked with the referential integrity are reduced in OODBMS and it gives an enhanced user metaphor than the relational model. Object oriented database can store both complex component and large structure. The large objects in object oriented database do not need to be broken apart and reassemble by application. Therefore object oriented data base do not suffer performance degradation.
RDBMS does not allow the nested structure. These category of applications widely found in CAD/CAE, aerospace, etc. But these applications are easily supported in OODBMS. Besides, it is better to deal with the complex structure in the form of objects rather than table, tuples and records in RDBMS.
Limited numbers of data types such as integer and string and limited number of built in operations are available in the relational database management system. This database management system is suitable for simple and few number of data types. The OODBMS on the other hand are appropriate for application where the relationships among elements in the database carry the key information.
According to the report we can takes some con-clusions regarding RDBMS and OODBMS:
â€¢ Relational databases have as their objective to ensure data independence ie> Normalized data is separated from processing and the processing corresponding to satisfy-ing informational requirements need not be totally pre-defined, thus accepting ad-hoc re-quirements too.
â€¢ Object oriented databases have as their main objective encapsulation, being stored together with the data and the methods. They are inseparable. It is said that we have to do with an independence of classes and not with an independence of data.
â€¢ An OODBMS and not an RDBMS is needed while in the reference applications we have to do with complex data.
â€¢ The object oriented database mar-kets will continue to develop, but they will still (represent) only a fraction of the traditional databases.
â€¢ It is appreciated that RDMSs hold the largest part of the largest part of the data-bases. But the prospect is that they will still co-exist for a long time future with the OODBS.
ORDBMS complicates database design due to its new richness. There are more alternative designs that can be used to represent a particular situation, and it is not always obvious which to pick. Unthinkingly applying some of these features, such as the COLLECTION columns, create problems.Order Now