Chapter 2, Problem 2.20RQ

Explanation of Solution

Referential integrity:

• Referential integrity is supported by Relational Database Management System (RDBMS).
• It created by aggregating foreign and primary keys.
• Relational database is basically a collection of tables where every table has a specific key assigned to it, which is known as a primary key.
  • In relational databases, a primary key is a key that is used for uniquely identifying and defining the characteristics of each row.
• The values in each row of a table are unique. Two tables are related to each other with the help of a foreign key.
  • A primary key attribute in one table is the foreign key for another table. In a logical way, a foreign key is used to establish a relationship between two tables.
• If the record in the referenced table is deleted then, all the records related to that referenced record will be deleted.

Example:

• It gives assurance for one value in an entity which is a foreign key attribute and will not get lost or disassociated from the parent entity...