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What is Relational Model

The relational model represents the database as a collection of relations. A relation is nothing but a table of values. Every row in the table represents a collection of related data values. These rows in the table denote a real-world entity or relationship.

The table name and column names are helpful to interpret the meaning of values in each row. The data are represented as a set of relations. In the relational model, data are stored as tables. However, the physical storage of the data is independent of the way the data are logically organized.

Some popular Relational Database management systems are:

• DB2 and Informix Dynamic Server - IBM
• Oracle and RDB – Oracle
• SQL Server and Access - Microsoft

The advantages and disadvantages of a relational model are as follows:

Advantages:

1. Relational model is easy to understand.
2. Data can be managed properly in it.
3. It provides structured query language to manage data, which is very easy to learn. DDL and DML are simpler in respect to the other models.
4. Transactions can be managed properly.
5. Many-to-many relationships can be represented through primary and foreign key and without any complexity.
6. Insert, delete, and update operations can be performed without any loss of data.
7. Data dictionary management is provided.

Disadvantage:

1. It is difficult to handle due to complex data types.

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