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A Database Management System (DBMS) is required to maintain and access
a computerised database.
DBMS is a software that enables the user to create a database and add,
modify, and delete data in it. It provides an interface that is both convenient
and efficient to use.
Database Management systems can be based on different data models. A
data model is a collection of concepts and rules for the description of the
structure of the database. Some examples of data models are Network,
Hierarchical, and Relational.
A Relational database is the most commonly used type of database model. It stores data in the form
of tables. A table organises data into rows called records and columns called fields. Each record in a
database contains data about one entity. Each field defines information of a certain type for all records.
Each table is given a unique name to identify it.
Let us view the structure of a table.
States of India

Name Capital Language Area (km )
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Uttar Pradesh Lucknow Hindi 240,928

Madhya Pradesh Bhopal Hindi 308,245

Maharashtra Mumbai Marathi 307,713

West Bengal Kolkata Bengali 88,752

The above table contains information about some states of India. It has four fields – Name, Capital,
Language, and Area, for the records – Uttar Pradesh, Madhya Pradesh, Maharashtra, and West Bengal.
A DBMS based on the relational model is known as Relational Database Management System (RDBMS).
Some popular relational database management systems include Microsoft Access 2019, IBM DB2,
Oracle, MySQL, and Microsoft SQL Server.
1. Controls Data Redundancy: Data redundancy refers to the duplication of data. In a DBMS, all
the data of an organisation is integrated into a single database file. Users access the centralised
database and do not maintain duplicate copies on their computers.

2. Facilitates Data Sharing : A DBMS stores data at a centralised location and facilitates sharing of
data among multiple users according to their requirements.
3. Controls Data Inconsistency : Data inconsistency exists when different versions of the same data
appear in different places. DBMS controls data inconsistency by updating the centralised database.
4. Ensures Data Integrity : A DBMS supports database integrity. Data integrity means that the data
updated in the database follows standard rules and formats for all users.
5. Ensures Data Security : A DBMS ensures data security and privacy. It allows creation of user accounts
and granting them various access rights to prevent unauthorised access and modification of data.

MICROSOFT ACCESS 2019
Microsoft Access 2019 is one of the most popular RDBMS. It provides tools to create, edit, and update
databases quickly and easily.

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