Write PL/SQL block to display students who have a grade of A. Write PL/SQL block to delete all students who are older than 18 years. Write PL/SQL block to retrieve the Name and Gra... Write PL/SQL block to display students who have a grade of A. Write PL/SQL block to delete all students who are older than 18 years. Write PL/SQL block to retrieve the Name and Grade of all students. Write PL/SQL block to sort Student id in reverse order. Write PL/SQL block to calculate factorial of numbers. Write PL/SQL block to print 9, 18, 27, 36, 45, ..., 90 number series. Read more

PL/SQL blocks provided for displaying, deleting, retrieving, sorting, factorials, and series printing as requested.

Here are the PL/SQL blocks for each task:

1. Display students with grade 'A':

DECLARE
BEGIN
    FOR student IN (SELECT * FROM Students WHERE Grade = 'A')
    LOOP
        dbms_output.put_line('ID: ' || student.ID || ', Name: ' || student.Name);
    END LOOP;
END;

2. Delete students older than 18:

BEGIN
    DELETE FROM Students WHERE Age > 18;
    COMMIT;
END;

3. Retrieve Name and Grade of all students:

DECLARE
BEGIN
    FOR student IN (SELECT Name, Grade FROM Students)
    LOOP
        dbms_output.put_line('Name: ' || student.Name || ', Grade: ' || student.Grade);
    END LOOP;
END;

4. Sort Student ID in reverse order:

DECLARE
BEGIN
    FOR student IN (SELECT * FROM Students ORDER BY ID DESC)
    LOOP
        dbms_output.put_line('ID: ' || student.ID || ', Name: ' || student.Name);
    END LOOP;
END;

5. Calculate factorial of numbers:

DECLARE
    n NUMBER := 5; --for example
    fact NUMBER := 1;
BEGIN
    FOR i IN 1..n LOOP
        fact := fact * i;
    END LOOP;
    dbms_output.put_line('Factorial of ' || n || ' is ' || fact);
END;

6. Print 9, 18, 27, ..., 90 series:

DECLARE
    i NUMBER;
BEGIN
    i := 9;
    WHILE i <= 90 LOOP
        dbms_output.put_line(i);
        i := i + 9;
    END LOOP;
END;