Comparative Study of ODBMS vs RDBMS

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International Journal of Research in Engineering Technology and Management
ISSN 2347 - 7539
Comparative Study of ODBMS vs RDBMS
Brahma Datta Shukla1, Dr. S. P. Singh2
1
P.hd Research Scholar, Department of Computer Science, NIMS, Jaipur, Rajasthan, INDIA
HOD & Associate Professor, Computer Science Engineering, NIMS, Jaipur, Rajasthan, INDIA, srigj@rediff mail.com
2
Abstract
In today environment it is very complicated to choose between the object oriented Model and the relational model, many factors
should be considered. The most important of these factors are single level and multilevel access controls, protection against
inference, and maintenance of integrity etc. When determining which distributed database model will be more secure for a
particular application, the decision should not be made purely on the basis of available security features. One should also
question the efficiency of the delivery of these features. Do the features provided by the database model provide adequate security
for the Intended application? Does the implementation of the security controls add an unacceptable amount of Computational
overhead? In this paper, we describe the object databases advantages and disadvantages over RDBMS. We also give the
description of implementation issues of object oriented databases.
Keywords: Data Model, OODBMS, RDBMS, Distributed Database Model etc.
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1. INTRODUCTION
As distributed system become more popular, the need for
improvement in distributed database management systems
becomes even more important. A distributed system varies
from a centralized system in one key respect: The data and
often the control of the data are spread out over two or more
geographically separate sites. Distributed database
management systems are subject to many security threats
additional to those present in a centralized database
management
system
(DBMS).
Furthermore,
the
development of adequate distributed database security has
been complicated by the relatively recent introduction of the
object-oriented database model.
For the last several years the most used database model has
been relational. While the relational model has been useful,
its utility is reduced if the data does not fit into a relational
table. Many organizations have data requirements that are
more complex than can be handled with these data types.
Multimedia data, graphics, and photographs are examples of
these complex data types.
1.1
INTRODUCTION
MODEL
TO
RELATIONAL
Relational databases typically treat complex data types as
BLOBs (binary large bjects). For many users, it is not
feasible because BLOBs cannot be queried. In addition,
database developers have impedance mismatch between the
third generation language (3GL) and structured query
language (SQL). The impedance mismatch occurs when the
3GL command set conflicts with SQL. There are two types
of impedance mismatches:
(1) Data type inconsistency: A data 1type recognized by
the relational database is not recognized by the 3GL. For
example, most 3GLs don’t have a data type for dates. In
order to process date fields, the 3GL must convert the date
into a string or a Julian date. This conversion adds extra
processing overhead.
(2) Data manipulation inconsistency: Most procedural
languages read only one record at a time, while SQL reads
records a set at a time. This problem is typically overcome
by embedding SQL commands in the 3GL code.
Solutions to both impedance problems add complexity and
overhead. Object-oriented databases have been developed in
response to the problems listed above: They can fully
integrate complex data types, and their use eliminates the
impedance mismatch.
The development of relational database security procedures
and standards is a more mature field than for the objectoriented model. This is principally due to the fact that
object-oriented databases are relatively new. The relative
immaturity of the object-oriented model is particularly
evident in distributed applications.
1.2 INTRODUCTION TO OBJECT ORIENTED
MODEL
Complex objects, object identity. Objects have arbitrary
complexity. Each object has identity, i.e. a unique internal
identifier (OID) (with no meaning in the problem domain),
and each object has one or more external names.
Relationships, associations, link. Objects are connected by
conceptual links. For instance, the Employee and
Department objects can be connected by a link works for
Encapsulation and information hiding. The internal
properties of an object are subdivided into two parts: public
and private (invisible from the outside).
Classes, types, interface. Each object is an instance of one or
more classes. Objects are instantiated according to
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Volume: 03 Issue: 05 | September-2015, Available @ http://www.ijretm.com | IJRETM-2015-03-05-006
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International Journal of Research in Engineering Technology and Management
information presented in the class. The class contains the
properties that are common for some collection of objects
(objects’ invariants). Each object has a type. Objects are
accessible via their interfaces.
Abstract data types (ADTs): a kind of a class, which
assumes that any access to an object is limited to the
predefined collection of operations. Operations, methods
and messages. An object is associated with a set of
operations (methods). The object performs the operation
after receiving a message with the name of operation to be
performed (and its parameters).
Inheritance & Classes are organized in a hierarchy reflecting
the hierarchy of real world concepts. For instance, the class
Person is a superclass of the classes Employee and Student.
Polymorphism, late binding & overriding. The operation to
be executed on an object is chosen dynamically, after the
obje ct receives the message with the operation name.
Persistence-Database objects are persistent, i.e., they live as
long as necessary. They can outlive, which created them.
2. RELATIONAL VS OBJECT DATABASE
OODBMS
ISSN 2347 - 7539
ORDBMS
It is created on the basis It is built by creating
of
persistent object-oriented
programming paradigm.
extensions of a relational
database system.
It supports ODL and OQL It supports an extended
for
defining
and form of SQL.
manipulating
complex
data types.
It aims to achieve
seamless integration with
object-oriented
programming languages
such as C++, Java, or
Smalltalk.
Such integration is not
required as SQL: 1999
allows us to embed SQL
commands in a host
language.
Query optimization is The relational model has
difficult to achieve in a very strong foundation
these databases.
for query optimization,
which helps in reducing
the time taken to
execute a query.
The query facilities of OQL
are
not
supported
efficiently
in
most
OODBMS.
The query facilities are
the main focus of
ORDBMS. The querying
in these databases is as
simple as in relational
database system, even
for complex data types
and multimedia data.
It is based on object- It
provides
good
oriented
programming protection
against
languages; any error of programming errors.
data type made by
programmer may affect
many users.
3. OBJECT DATABASE
OVER RDBMS
ADVANTAGES
These are main advantages of object database over
RDBMS is following:
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Volume: 03 Issue: 05 | September-2015, Available @ http://www.ijretm.com | IJRETM-2015-03-05-006
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International Journal of Research in Engineering Technology and Management







Objects don't require assembly and disassembly
saving coding time and execution time to assemble
or disassemble objects.
Reduced paging
Easier navigation
Better concurrency control - A hierarchy of objects
may be locked.
Data model is based on the real world.
Works well for distributed architectures.
Less code required when applications are object
oriented.


ISSN 2347 - 7539
Return control to the program, transparently
retrying the instruction that caused the page
fault.
Easy to maintain
4. OBJECT DATABASE DISADVANTAGES
COMPARED TO RDBMS
These are main disadvantages of object database over
RDBMS is following:






Lower efficiency when data is simple and
relationships are simple.
Relational tables are simpler.
Late binding may slow access speed.
More user tools exist for RDBMS.
Standards for RDBMS are more stable.
Support for RDBMS is more certain and change is
less likely to be required.
5.
OBJECT
ORIENTED
IMPLEMENTATION ISSUES
DATABASE
There are following issues are used to implement object
oriented database.
 Persistence
 Sharing
 Paging
 Back to the Beginning
Object-oriented databases give objects persistence, which
enables objects to be stored between database runs. In
Object Oriented, paging is one of the memory-management
schemes by which a object oriented database can store and
retrieve data from secondary storage for use in main
memory.
In the paging memory-management scheme, the operating
system retrieves data from secondary storage in same-size
blocks called pages.
The main advantage of paging over memory segmentation is
that it allows the physical address space of a process to be
noncontiguous. Before the time paging was used, systems
had to fit whole programs into storage contiguously, which
caused various storage and fragmentation problems.
There are following advantages of paging in object oriented
database Determine the location of the data in auxiliary
storage.
 Load the requested data into the available page
frame.
 Update the page table to show the new data.
Fig-1: Objects Shared Between Processes
Object-oriented databases allow objects to be shared
between processes in a distributed environment.
Fig-2: Object Sharing
Object-oriented databases can reduce the need for paging by
enabling only the currently required objects to be loaded
into memory (relational databases load in tables containing
both the required data AND other unnecessary data)
6. CONCLUSIONS
In this paper, we provide the detail characteristics of
database by which it is used means mandatory, optional &
open. We provide the Object Database Advantages over
RDBMS, Object Database Disadvantages compared to
RDBMS, Object Oriented Database Standards, How object
oriented database is implemented. We also provide how do
ODBMS & RDBMS Work & Implementation Issues, benefits
& drawbacks of Distributed Database.
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Volume: 03 Issue: 05 | September-2015, Available @ http://www.ijretm.com | IJRETM-2015-03-05-006
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International Journal of Research in Engineering Technology and Management
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Volume: 03 Issue: 05 | September-2015, Available @ http://www.ijretm.com | IJRETM-2015-03-05-006
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