What is a DBMS

1. What is a DBMS?

A database management system (also known as DBMS) is a software used to store and retrieve user data by taking into account appropriate security measures, allowing users to create their own databases as per their requirements. A DBMS consists of a set of programs, and the programs manipulate the database and provide an interface between the databases. The DBMS includes users of the database and other applications. The DBMS accepts data requests from applications and instructs the operating system to provide specific data. In large systems, DBMS helps users and other third-party software store and retrieve data.

2. Characteristics of DBMS database management system

1. Provide security and eliminate redundancy

2. Self-describing nature of the database system

3. Isolation between program and data abstraction

4. Support multiple data views

5. Shared data and multi-user transaction processing

6 .DBMS allows entities and the relationships between them to form tables.

7.DBMS supports multi-user environment, allowing users to access and operate data in parallel.

3. Four types of DBMS

1. Hierarchical DBMS

In a hierarchical database, model data is organized in a tree structure. Data is stored in a hierarchical (top-down or bottom-up) format. Data is represented using parent-child relationships. In Hierarchical DBMS, a parent may have many children, but a child has only one parent.

2. Network model

The network database model allows each child to have multiple parents. It helps you address your need to model more complex relationships, such as order/part many-to-many relationships, where entities are organized graphically and can be accessed through multiple paths.

3. Relational Model

Relational DBMS is the most widely used DBMS model because it is one of the simplest models. This model is based on normalizing data in table rows and columns. Relational models are stored in fixed structures and manipulated using SQL.

4. Object-oriented model

The object-oriented model data is stored in the form of objects. A structure called a class in which data is displayed. It defines a database as a collection of objects that store data member values ​​and operations.

Four: Disadvantages of DBMS

DBMS may provide many advantages, but it also has certain disadvantages. The hardware and software costs of DBMS are very high, which increases the cost budget. , and most database management systems are usually complex systems, so users need to learn how to use DBMS. In some organizations, all data are integrated into one database, which may occur due to electrical failure or damage to the database on the storage medium. Can get corrupted and using the same program by many users at one time sometimes results in loss of some data.

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