Live ORACLE

DECLARE

  grade       CHAR(1) := 'B';

   appraisal   VARCHAR2(120);

   id          NUMBER := 8429862;

   attendance  NUMBER := 150;

   min_days  CONSTANT NUMBER := 200;

   FUNCTION Attends_this_school

        (id  NUMBER)

   RETURN BOOLEAN

   IS

   BEGIN

     RETURN true;

   END;

BEGIN

  appraisal := CASE

                 WHEN Attends_this_school(id) = false THEN  'N/A - Student not enrolled'

                 -- Have to test this condition early to detect good students with bad attendance

                 WHEN grade = 'F'

                       OR attendance < min_days THEN  'Poor (poor performance or bad attendance)'

                 WHEN grade = 'A' THEN  'Excellent'

                 WHEN grade = 'B' THEN  'Very Good'

                 WHEN grade = 'C' THEN  'Good'

                 WHEN grade = 'D' THEN  'Fair'

                 ELSE 'No such grade'

               END;

 

  dbms_output.Put_line('Result for student '

                       ||id

                       ||' is '

                       ||appraisal);

END;

/

Using a Search Condition With a CASE Statement