A name given to a block of code which allows access to the variables that have scope, but are not visible.

Consists of all the blocks in which the variable is either local (the declaring block) or global (nested blocks within the declaring block) .

The portion of the program where the variable can be accessed without using a qualifier.

Try It / Solve It

1. Evaluate the PL/SQL block below and determine the value of each of the following variables according to the rules of

DECLARE

weight NUMBER(3) := 600; message VARCHAR2(255) := 'Product 10012';

BEGIN

DECLARE weight NUMBER(3) := 1; message VARCHAR2(255) := 'Product 11001'; new_locn VARCHAR2(50) := 'Europe'; BEGIN weight := weight + 1; new_locn := 'Western ' || new_locn; -- Position 1 --

scoping.

DECLARE

weight NUMBER(3) := 600; message VARCHAR2(255) := 'Product 10012';

BEGIN

The value of weight at position 2 is:

D. The value of message at position 2 is:

E. The value of new_locn at position 2 is:

2. Enter and run the following PL/SQL block, which contains a nested block. Look at the output and answer the questions.

DECLARE

v_employee_id employees.employee_id%TYPE; v_job employees.job_id%TYPE;

BEGIN

SELECT employee_id, job_id INTO v_employee_id, v_job FROM employees WHERE employee_id = 100;

DECLARE v_employee_id employees.employee_id%TYPE; v_job employees.job_id%TYPE;

BEGIN

SELECT employee_id, job_id INTO v_employee_id, v_job FROM employees WHERE employee_id = 103;

DBMS_OUTPUT.PUT_LINE(v_employee_id || ' is a(n) ' || v_job);

END;

DBMS_OUTPUT.PUT_LINE(v_employee_id || ' is a(n) ' || v_job);

END; A. Why does the inner block display the job_id of employee 103, not employee 100?

B. Why does the outer block display the job_id of employee 100, not employee 103?

C. Modify the code to display the details of employee 100 in the inner block. Use block labels.