Architecture of DBMS and RDBMS

https://www.computersprofessor.com/2016/04/architecture-of-dbms-and-rdbms.html
DBMS AND RDBMS
DBMS ARCHITECTURE:
A data base is an organized collection of
information. It consists of all the files in an organized manner therefore
database is a structured and integrated system to facilitate upto-date
information. Technically, a data base consist all the files in the data base
management system as an integral part.
A DBMS requires to
perform variety of operations, when the user requests the system to perform
operations, which are as follows…..
- Adding new records into the data base.
- Modifying the data in the existing files
- Retrieving data from the files
- Deleting the data from the files
- Searching the data from the files, upon a condition
- Removing the files from the database
A data base whose over all
purpose is, to store information and allow the users to retrieve and update the information.
DBMS is divided into
four main components such as,
1. Data
2. Hard ware
3. Soft ware
4. Users
Data:
Data is referred to what is actually stored
in the database & information refers
to the meaning of that data as understood by the users. The data base systems are available on the
machines that ranges all the way from a small p.c to the large mainframes this
facility is provided by any given system
is determined by the size & power of the machine. A multi- user system is a
system in which many users can access the data at the same time.
HARDWARE:
Hard
ware components of a system consists of
1. Hardware processor with a
database system software
2. Secondary storage devices
3. Typically the magnetic
discs & magnetic tapes, used to hold the data together with I/o devices,
device controllers etc.
SOFTWARE:
The data is physically stored in the database
& the users of the system is a layer of the software known as DBMS OR
database server.
All the requests to accesses the database are
handled by DBMS.
USERS:
The users are broadly classified
into 3 types ,
1.
APPLICATION PROGRAMMERS
2.
END USERS
3.
DATABASE ADMINISTRATORS
The application users are responsible
for writing database application
programs in some programming languages such as COBOL,C,C++ etc. Such programs access the database by issuing the
appropriate request.
The end users are those who access the
database interactively. The database system has built in applications called
QUERY LANGUAGE processors by which the users can access the database through a
request by using commands.
The database administrator is an associated data administration functions.
Thus, the advantage of database
systems are, used due to its,
1. Speed
2. Accuracy
3. Up to-date information
4. Compactness
5.
Protection
6. Reliability and
7. Security
ADVANTAGES OF DATABASE:
1. A DATA
BASE CAN BE SHARED:
Sharing
means not only existing application that can
share the data Iin a database
system but also a new application can be developed to operate against
the same data.
2. REDUNDANCY
CAN BE REDUCED:
Redundancy
means, repetition or duplication of data. In non-database systems, each application has
its own private fields. This fact will lead a redundancy in the stored data. This resultant waste is stored & it may
lead to inconsistency.
3. INCONSISTENCY CAN BE AVOIDED:
The
DBMS is not aware of the duplication of the data. When there will be an occasion of redundancy
and therefore, can’t be updated in the database when you modify the data once.
Thus the data base is said to be inconsistent.
4. TRANSACTION SUPPORT CAN BE
PROVIDED:
A
transaction is a logical unit of work involving several database operations For
example, the transfer of cash account from one account to another account.
5. INTEGRITY CAN BE MAINTAINED:
Integrity
means ensuring the correct data in a database. Integrity problem can arise only if redundancy
exists in the stored data.
6. SECURITY CAN BE ENFORCED:
The data base manager or DBA can
ensure that the only means of accessing the database is through proper channel
& hence you can define the security constraints whenever an access is attempted
to reach the sensitive data.
7. CONFLICTING REQUIREMENTS CAN BE
BALANCED:
When
you know the overall requirements of the organization, the DBA can be structured
in such a way so as to provide overall services
8. STANDARDS CAN BE ENFORCED:
With
the central control of database, the DBA can ensure that all the applicable
standards are observed in the representation of data.
9. DATABASE ADMINISTRATION:
The
DBA decides what data should be stored in the data & the policies for
maintaining the database. An example of
such policy in dealing with the data is security. A DBA is responsible for
ensuring a system that operates with an adequate performance & provide a
variety of other technical services for most important applications.
RDBMS:
A
data base is a persistent & meaningful data .A relational database
management is a dbms that is based on the relational model introduced by Dr. EDGER
F CODD. A RDBMS stores the data in the form of related tables .RDBMS software’s are
powerful because they require few
assumptions about how a data is related
& the way how a data ia extracted from the database . As a result
the same data can be viewed in many different ways.
The
common language to access the data in a database is ‘structured query language’
(SQL) and hence, it is an interface to RDBMS .SQL can be pronounced as, SEQUEL
which is developed in the year 1970 by IBM. It has become the standard language
used to inter act the RDBMS software’s such as ORACLE, SYBASE etc.