Chapter 4, Problem 15CAT

Program Plan Intro

“SELECT” command:

The “SELECT” command is used to retrieve data in a database.

Syntax for selecting values from the table is as follows:

SELECT STUDENT_ID FROM STUDENT;

• The given query is used to display each student ID from “STUDENT” table.

“DISTINCT” Operator:

• Using “DISTINCT” operator, user can eliminate the duplicate values in a query’s results.

Example:

The example for “DISTINCT” operator is given below:

SELECT DISTINCT(STUDENT_ID) FROM STUDENTS;

The above query is used to list number of each student ID only once using “DISTINCT” operator.