It will be helpful to reiterate our database definition here, that is, database is a shared
collection of logically related data, designed to meet the information needs of multiple
users in an organization. A typical database system environment is shown in the figure 3
below:
A typical Database System environment
The figure shows different subsystem or applications in an educational institution, like
library system, examination system, and registration system. There are separate, different
application programs for every application or subsystem. However, the data for all
applications is stored at the same place in the database and all application programs,
relevant data and users are being managed by the DBMS. This is a typical database
system environment and it introduces the following advantages:
o Data Sharing
The data for different applications or subsystems is placed at the same place. This
introduces the major benefit of data sharing. That is, data that is common among
different applications need not to be stored repeatedly, as was the case in the file
processing environment. For example, all three systems of an educational institution
shown in figure 3 need to store the data about students. The example data can be seen
library system, examination system, and registration system. There are separate, different
application programs for every application or subsystem. However, the data for all
applications is stored at the same place in the database and all application programs,
relevant data and users are being managed by the DBMS. This is a typical database
system environment and it introduces the following advantages:
o Data Sharing
The data for different applications or subsystems is placed at the same place. This
introduces the major benefit of data sharing. That is, data that is common among
different applications need not to be stored repeatedly, as was the case in the file
processing environment. For example, all three systems of an educational institution
shown in figure 3 need to store the data about students. The example data can be seen
from figure 2. Now the data like registration number, name, address, father name that
is common among different applications is being stored repeatedly in the file
processing system environment, where as it is being stored just once in database
system environment and is being shared by all applications. The interesting thing is
that the individual applications do not know that the data is being shared and they do
not need to. Each application gets the impression as if the data is being for stored for
it. This brings the advantage of saving the storage along with others discussed later.
o Data Independence
Data and programs are independent of each other, so change is once has no or
minimum effect on other. Data and its structure is stored in the database where as
application programs manipulating this data are stored separately, the change in one
does not unnecessarily effect other.
o Controlled Redundancy
Means that we do not need to duplicate data unnecessarily; we do duplicate data in
the databases, however, this duplication is deliberate and controlled.
o Better Data Integrity
Very important feature; means the validity of the data being entered in the database.
Since the data is being placed at a central place and being managed by the DBMS, so
it provides a very conducive to check or ensure that the data being entered into the
database is actually valid. Integrity of data is very important, since all the processing
and the information produced in return are based on the data. Now if the data entered
is not valid, how can we be sure that the processing in the database is correct and the
results or the information produced is valid? The businesses make decisions on the
basis of information produced from the database and the wrong information leads to
wrong decisions, and business collapse. In the database system environment, DBMS
provides many features to ensure the data integrity, hence provides more reliable data
processing environment.
Dear students, that is all for this lecture. Today we got the introduction of the course,
importance of the databases. Then we saw different definitions of database and studied
what is data processing then studied different features of the traditional file processing
environment and database (DB) system environment. At the end of lecture we were
discussing the advantages of the DB approach. There some others to be studied in the
next lecture. Suggestions are welcome.
is common among different applications is being stored repeatedly in the file
processing system environment, where as it is being stored just once in database
system environment and is being shared by all applications. The interesting thing is
that the individual applications do not know that the data is being shared and they do
not need to. Each application gets the impression as if the data is being for stored for
it. This brings the advantage of saving the storage along with others discussed later.
o Data Independence
Data and programs are independent of each other, so change is once has no or
minimum effect on other. Data and its structure is stored in the database where as
application programs manipulating this data are stored separately, the change in one
does not unnecessarily effect other.
o Controlled Redundancy
Means that we do not need to duplicate data unnecessarily; we do duplicate data in
the databases, however, this duplication is deliberate and controlled.
o Better Data Integrity
Very important feature; means the validity of the data being entered in the database.
Since the data is being placed at a central place and being managed by the DBMS, so
it provides a very conducive to check or ensure that the data being entered into the
database is actually valid. Integrity of data is very important, since all the processing
and the information produced in return are based on the data. Now if the data entered
is not valid, how can we be sure that the processing in the database is correct and the
results or the information produced is valid? The businesses make decisions on the
basis of information produced from the database and the wrong information leads to
wrong decisions, and business collapse. In the database system environment, DBMS
provides many features to ensure the data integrity, hence provides more reliable data
processing environment.
Dear students, that is all for this lecture. Today we got the introduction of the course,
importance of the databases. Then we saw different definitions of database and studied
what is data processing then studied different features of the traditional file processing
environment and database (DB) system environment. At the end of lecture we were
discussing the advantages of the DB approach. There some others to be studied in the
next lecture. Suggestions are welcome.
👌👍
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