Relational Data Model With Concepts

In this post, we will talk about the Relational data model of class 11th so let's start and know first what is Data? and what is the Database? so Data is our basic information, and a Database is a place where stored the information or data this is called the database.

Above we have learned about the Database, now we will discuss the Types Of Database. Well, the database is many types but in this blog,  we will talk about the Relational Data Model according to the CBSE class 11th IP syllabus.

let us know some important types of Database -

• Hierarchical database
• Relational database
• Network database 
• Graphical database
• Object-oriented database
• ER model database

What Is Relational Data Model and Definition of the relational data model

We all know the meaning of Relation. Relation means a Connection. Relational Data Model represents the relationship or connection between the tables. Every row in the table represents the connection between the data. This Model stores the data in the form of tables. Every table consists of Rows and Columns.

All tables are interconnected to each other through a Foreign Key.

Concept of the Relational data model?

You must have understood the Relational data model, now let's talk about the concept. By the way many concepts of relational data models but here we learn about these 6 concepts covering CBSE class 11th syllabus. The relational data model uses the following basic concepts.

• Relation
• Tuples / Records / Rows
• Attribute / Fields / Column
• Domain
• Cardinality 
• Degree

1) What Is Relation?

You will be very well aware of all the Database Tables which contain ROWS and COLUMNS. So here we say in simple words  A relation in a database means a ‘TABLE’. This table has some properties.

• Every column is unique. It does not contain duplicate data.
• Every row must be unique, Means will be the same value in one row.

2) What Is Tuple?

Now we talk about the Tuple. It is very easy to understand the tuples Each Row in a Table is called Tuple or Record. One Row means One Tuple or Record.

You can see this example where you are seeing 4 Rows so that means these are the 4 tuples.

3) What Is Attribute?

Now know about Attribute, Each column in a Table is called Attribute or Field. One column means one Attributes

Look at this table here, How many Columns in this table? You will see 4 Columns that mean 4 Attributes or Fields.

3) What Is Domain?

A domain is a unique set of values. Each domain contains a set of data related to a specific purpose.

Here you will see 2 Examples -:

1st Example -: Gender

Whenever you filled any form then you fill this category(Gender), this category values(Male, Female, others) are fixed, you cant change so its set or pool is called a domain.

2st Example -: Days

Similarly, the days and Months is also fixed so its set called domain.

4) What Is Cardinality?

We have already learned about tuple, Now we will know cardinality. The total number of Tuples / Records which in the relation is called the Cardinality.

There is a table here and this table has 4 4Rows, so the total number of rows is called Cardinality.

5) What Is Degree?

We have already learned about Attribute, Now we will know the Degree. The total number of attributes in the relation is called the degree.

There is a table here and this table has  4 Columns, so the total number of rows is called Degree.