A DBMS Makes The : Collection Of Data Set Of Program

A DBMS makes the collection of data or a set of programs to manipulate data stored in a database. that’s called database management system or DBMS. A database management system provides basic functionalities like storage manipulation or user of data.

There are four major components of the database management system which form of the database system environment as listed below.

HOW A DBMS MAKES THE SET OF PROGRAM

• Data
• Hardware
• Software
• Users

The following figure depicts these four components. These components are described in the following sub-sections.

Data

The collection of related data is referred to as a database. In other words, the database is a repository of related data. Integrated data means they are correct and consistent.

Correctness suggests that data satisfies the integrity rules, such as balance should not be negative.

Consistency suggests that all the data stored in a database should be consistent. For example, an account should not have a branch name that does not exist.

Depending upon the number of users interacting with the system. a database system can be a single user system or multi-user system. In a single-user system, at most one user can access the database at a time. In a multi-user system, more than one user can access the database at the same time.

Hardware

All the physical devices of a computer system are referred to as hardware. A computer system can have several different hardware such as processor, memory, hard disk, monitor, keyboard, mouse, printer, scanner, etc.

From a database system point of view, important hardware can be divided into two categories:

processor and main memory – Supports the execution of the database software.

secondary storage device – Used to store data of a system or organization permanently.

These include hard disks, magnetic tapes, compact disks, etc.

Hard disks are the most widely used secondary storage devices nowadays.

Software

The software provides the interface between users and databases stored in physical devices. Application programs, DBMS software, and operating systems from the software component here.

The operating system manages all the hardware of the computer. The file system of the operating system provides interaction between other software components and hardware such as a hard disk.

User

These are the four main categories of database users:

•        Database Administrator – He/She is responsible for the proper functioning of the database system.

•        Database designers – Identify the data to be stored in a database and designs the structure of the database for an organization.

•        End users – These users interact with the database in different manners depending upon their requirements.

Advantages Of DBMS

database management system contains centralized management and control over the database. Also, DBMS software is used to provide interaction between application programs and databases. Due to this, it provides many advantages. These advantages are given below.

Minimal Data Redundancy

possible to avoid unnecessary duplication of information. For example, all the information about bank customers can be kept centralized. This prevents unnecessary duplication of customer information who has both types of accounts.

leads to reduced data redundancy. Reduced data redundancy prevents memory. wastage.

Improved Data Consistency

inconsistency occurs due to data redundancy. For example, consider that customer requirement is maintained separately for savings accounts and current accounts.   

Efficient Data Access

Utilizes a variety of techniques to retrieve data. Required data can be retrieved by providing an appropriate query to the DBMS.   

The data can be accessed in a convenient and efficient manner.

Improved Data Sharing

the database is maintained centrally, all authorized users and application programs can share this database easily.

Improved Data Integrity

the software provides different ways to implement such type of constraints. Also, it ensures that the data stored in the database follows such constraints on its own. Application programs need not worry about this.

Guaranteed Atomicity

operation on a database must be atomic. This means it must happen in its entirety or not at all. For example, a fund transfer from one account to another must happen in its entirety.

That is the responsibility of the DBMS software to ensure such a kind of atomicity. If any operation fails due to some problems, such as system crashes, then the effects of the partially executed operation can be undone.

In database systems, atomicity can be guaranteed.

Improved Security

For example, a customer can check balance only for his/her account.

the software provides a way to control access to data for different users according to their requirements.

It provides several advantages over other database systems, such as file-oriented systems, as described in the previous section. In spite of this, DBMS contains some drawbacks. The following are the disadvantages of using DBMS.

Disadvantages Of DBMS

High Cost

the initial cost is required to implement database and application programs.

incurs high initial cost behind DBMS software. Also, hardware needs to be upgraded according to the requirements of the DBMS software.

from older file-oriented system to a database system is also costly in terms of money as well as time.

Specialized Manpower

The system requires specialized, skilled manpower to design & develop databases and to provide database administration services.

due to rapid changes in database technology. this manpower needs to be trained and retrained regularly

Security Risks

It is kept centrally and can be used by multiple users remotely at the same time requires to authorize access to data among users to prevent misuse of confidential and important data.

Increased Complexity

It is necessary to understand the requirements of the organization and different kinds of users to design and implement an efficient database.

Need for Explicit Backup and Recovery

the entire database is maintained centrally, it is must to provide efficient backup and recovery facilities.

all these drawbacks, it becomes quite essential to decide whether to use a database system or to use a file-oriented system.

It is desirable not to use database systems if the – database is simple & well-defined, need not change frequently, and concurrent access among multiple users is not required.