File systems versus a dbms

 What is traditional file system?
 Overview of traditional file system.
 Advantages of traditional file system.
 Limitations of traditional file system.
 What is DBMS?
 Overview of DBMS.
 Components of DBMS.
 Advantages of DBMS.
 Limitations of DBMS
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 In a typical file processing system, each
department has its own set of applications and
its own files, designed specifically for those
applications.
 The department itself ,working with the data
processing staff, set policies or standards for
the format and maintenance of its files.
 Computer readable data in file system are kept
in files stored on magnetic tape or disk.
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 For example:
To illustrate Traditional File Processing
Systems definition, lets us take an example
of college where student record for
examination is stored in one file, admission
records on other file and library record is
stored in different file that creates many
duplicate values like roll Number, Name
and Father Name
that creates data redundancy.
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 It stores data of an organization in group of files.
 Files carrying data are independent on each other.
 COBOL, C, C++ programming languages were used to design the
files.
 Each file contains data for some specific area or department like
library, student fees, and student examinations.
 It is less flexible and has many limitations.
 It is very difficult to maintain file processing system.
 Any change in one file affects all the files that creates burden on
the programmer.
 File in Traditional File Processing Systems are called flat files.
NOTE:-A flat file stores data in plain text format. In a relational
database, a flat file includes a table with one record per line. The
different columns in a record are delimited by a comma or tab to
separate the fields. Data stored in flat files have no folders or paths
associated with them.
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 Companies mainly use file processing to handle large
volumes of structured data on a regular basis
 File processing design approach was well suited to
mainframe hardware and batch input
 File processing can be more efficient and cost less than a
DBMS in certain situations
 The design of file processing is more simple than
designing Database
 File processing cost less and can be more speed than
Database
 We can customize file processing more easily and
efficiently than Database because files are related with
the application and it have all the data needed for that
application
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 Separated and Isolated Data: To make a decision, a user might
need data from two separate files. First, the files were evaluated by
analysts and programmers to determine the specific data required
from each file and the relationships between the data and then
applications could be written in a programming language to process
and extract the needed data. Imagine the work involved if data from
several files was needed.
 Duplication of data: Often the same information is stored in more
than one file, that requires additional storage space, more costs time
and money to enter the data more than once.
 Duplication can lead to loss of data integrity
Data Dependence: in file based approach application programs
are data dependent. It means that, with the change in the physical
representation (how the data is physically represented in disk) or
access technique (how it is physically accessed) of data,
application programs are also affected and needs modification. In
other words application programs are dependent on the how the
data is physically stored and accessed.
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Data Redundancy: occurs when data common to two or more
information systems is stored in several places. Data redundancy
requires more storage space, and maintaining and updating data
in several locations is expensive.
Data Integrity: Refers to the validity of data. Data integrity
can be compromised in a number of ways: human errors when
data is entered, errors that occur when data is transmitted from
one computer to another, software bugs or viruses, hardware
malfunctions, such as disk crashes and natural disasters, such
as fires and floods.
Rigid Data Structure: A data structure that is hard to work with
and inflexible. File-processing is rigid when compared to a
typical database management system.
Data inconsistency: The same attribute may have different
values.
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 Simplicity: the design of file processing is more simple than designing
Database
 Efficiency: file processing cost less and can be more speed than
Database
 Customization: you can customize file processing more easily and
efficiently than Database because files are related with the application
and it have all the data needed for that application
 Difficulty in representing data from the user's view: To create
useful applications for the user, often data from various files must be
combined. In file processing it was difficult to determine relationships
between isolated data in order to meet user requirements.
 Data Inflexibility: Program-data interdependency and data isolation,
limited the flexibility of file processing systems in providing users with
ad-hoc information requests
Data Security. The security of data is low in file based system
because, the data is maintained in the flat file(s) is easily
accessible.
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 Incompatible file formats: As the structure of files is embedded in the
application programs, the structures are dependent on the application
programming language. For example, the structure of a file generated by
a COBOL program may be different from the structure of a file generated
by a 'C' program. The direct incompatibility of such files makes them
difficult to process jointly.
 Transactional Problems: The File based system approach does not
satisfy transaction properties like Atomicity, Consistency, Isolation and
Durability properties commonly known as ACID properties.
 Concurrency problems: When multiple users access the same piece of
data at same interval of time then it is called as concurrency of the
system. When two or more users read the data simultaneously there is
no problem, but when they like to update a file simultaneously, it may
result in a problem.
 Poor data modeling of real world: The file based system is not able to
represent the complex data and relationships, which results poor data
modeling properties.
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 A Database Management System (DBMS) is a system software that
allows users to efficiently define, create, maintain and share
databases.
 Defining a database involves specifying the data types, structures and
constraints of the data to be stored in the database.
 Creating a database involves storing the data on some storage
medium that is controlled by DBMS.
 Maintaining a database involves updating the database whenever
required to evolve and reflect changes in the database and also
generating reports for each change.
 Sharing a database involves allowing multiple users to access the
database.
 DBMS also serves as an interface between the database and end
users or application programs. It provides control access to the data
and ensures that data is consistent and correct by defining rules on
them.
An application program accesses the database by sending queries or
requests for data to the DBMS. A query causes some data to be
retrieved from database.
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MySQL Database
MS- Access
Oracle Database
Microsoft SQL Server
File Maker
NoSQL
Postgresql
MS Fox Pro
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 Software for creating and maintaining databases
 Permits firms to rationally manage data for the
entire firm
 Acts as interface between application programs
and physical data files
 Separates logical and design views of data
 Solves many problems of the traditional data file
approach
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› Because DBMSs are powerful, they require more
expensive hardware, software, and data
networks capable of supporting a multi-user
environment
› More complex than a file processing system
› Procedures for security, backup, and recovery
are more complicated and critical
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• Data definition language: Specifies content
and structure of database and defines each
data element
• Data manipulation language: Used to process
data in a database
• Data dictionary: Stores definitions of data
elements and data characteristics
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 Scalability: Scalability means that a system can be
expanded, modified, or downsized easily to meet the rapidly
changing needs of a business enterprise. Also known as
extensibility.
 Better support for client/server systems: In a
client/server system, processing is distributed throughout an
organization. Client/server systems require the power and
flexibility of database design.
 Economy of sale: The inherent efficiency of high-volume
processing on larger computers. Database design allows
better utilization of hardware. If a company maintains an
enterprise-wide database, processing is less expensive using
a powerful mainframe server instead of using several smaller
computers.
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 Flexible data sharing: Data can be shared across the
enterprise, allowing more users to view the same information
in different ways
 Enterprise-wide application-database
administrator(DBA): (DBA) typically manages a
database management system (DBMS). The DBA assesses
overall requirements and maintains the database for the
benefit of the entire organization rather than a single
department or user.
 Stronger Standards: effective database administration
helps ensure that standards for data names, formats, and
documentation are followed uniformly throughout the
organization
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 Controlled redundancy: because the data is stored in a
set of related tables, data items do not need to be duplicated
in multiple locations
 Better Security: the DBA defines authorization
procedures to ensure that only legitimate users can access
the database and can allow different users to have different
levels of access
 Increased programmer productivity: programmers
do not have to create the underlining file structure for the
database, so they can concentrate on logical design
 Data Independence: systems that interact with a DBMS
are relatively independent of how the physical data is
maintained
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High Cost of DBMS:A DBMS is a large and
sophisticated piece of software ,it is expensive to
purchase or lease.
Higher hardware cost: Additional memory and
processing power may be required to run the
DBMS, resulting in need to upgrade hardware.
Higher programming cost: A DBMS is complex
tool with many features ,programmer’s should have
thorough knowledge to use the system, for this
organization has to pay extra for expertise.
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High conversion cost: different formats are
used in files, when an organization converts to a
database system, data has to be removed from
files and loads into the database, this may be
difficult and time consuming.
Increased vulnerability: As we know that in
DBMS, all the files are stored in single database
so chances of database failure become more.
Any accidental failure of component may cause
loss of valuable data
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File systems versus a dbms