DEFINE Command

Description:
Use the DEFINE command to create and assign a value to a variable.
Use the UNDEFINE command to remove a variable.

Examples:

DEFINE employee_num = 200

SELECT employee_id, last_name, salary

FROM   employees

WHERE  employee_id = &employee_num ;

UNDEFINE employee_num

The example creates a substitution variable for an employee number by using the DEFINE command. At run time, this displays the employee number, name and salary for that employee.

Because the variable is created using the SQL Developer DEFINE command, the user is not prompted to enter a value for the employee number. Instead, the defined variable value is automatically substituted in the SELECT statement.

The EMPLOYEE_NUM substitution variable is present in the session until the user undefines it or exits the SQL Developer session.