Common Relational Database Operations
In this lesson, we will look at some of the different operations that can be performed on relational databases.
We'll cover the following...
We will concentrate on the three basic operations that can change the states of relations in the database: Insert, Delete, and Update. Insert is used to insert one or more new tuples in a relation, Delete is used to delete tuples, and Update is used to change the values of some attributes in existing tuples.
Whenever these operations are applied, the integrity constraints specified on the relational database schema should not be violated. So we will also discuss the types of constraints that may be violated by each of these operations along with the types of actions that may be taken if an operation causes a violation.
We will be using the database state illustrated below:
EMPLOYEE
| Name | Ssn | Bdate | Salary | Super_Ssn | Dept_Num |
|---|