Use a user-defined function in stored procedure
SQL> CREATE TABLE lecturer (
2 id NUMBER(5) PRIMARY KEY,
3 first_name VARCHAR2(20),
4 last_name VARCHAR2(20),
5 major VARCHAR2(30),
6 current_credits NUMBER(3)
7 );
Table created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10001, 'Scott', 'Lawson','Computer Science', 11);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major, current_credits)
2 VALUES (10002, 'Mar', 'Wells','History', 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10003, 'Jone', 'Bliss','Computer Science', 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10004, 'Man', 'Kyte','Economics', 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10005, 'Pat', 'Poll','History', 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10006, 'Tim', 'Viper','History', 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10007, 'Barbara', 'Blues','Economics', 7);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10008, 'David', 'Large','Music', 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10009, 'Chris', 'Elegant','Nutrition', 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10010, 'Rose', 'Bond','Music', 7);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10011, 'Rita', 'Johnson','Nutrition', 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
2 VALUES (10012, 'Sharon', 'Clear','Computer Science', 3);
1 row created.
SQL>
SQL>
SQL>
SQL> CREATE TABLE session (
2 department CHAR(3),
3 course NUMBER(3),
4 description VARCHAR2(2000),
5 max_lecturer NUMBER(3),
6 current_lecturer NUMBER(3),
7 num_credits NUMBER(1),
8 room_id NUMBER(5));
Table created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('HIS', 101, 'History 101', 30, 11, 4, 20000);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('HIS', 301, 'History 301', 30, 0, 4, 20004);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('CS', 101, 'Computer Science 101', 50, 0, 4, 20001);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('ECN', 203, 'Economics 203', 15, 0, 3, 20002);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('CS', 102, 'Computer Science 102', 35, 3, 4, 20003);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('MUS', 410, 'Music 410', 5, 4, 3, 20005);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('ECN', 101, 'Economics 101', 50, 0, 4, 20007);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('NUT', 307, 'Nutrition 307', 20, 2, 4, 20008);
1 row created.
SQL>
SQL> INSERT INTO session(department, course, description, max_lecturer, current_lecturer, num_credits, room_id)
2 VALUES ('MUS', 100, 'Music 100', 100, 0, 3, NULL);
1 row created.
SQL>
SQL>
SQL> CREATE TABLE myStudent (
2 student_id NUMBER(5) NOT NULL,
3 department CHAR(3) NOT NULL,
4 course NUMBER(3) NOT NULL,
5 grade CHAR(1)
6 );
Table created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
2 VALUES (10000, 'CS', 102, 'A');
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
2 VALUES (10002, 'CS', 102, 'B');
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
2 VALUES (10003, 'CS', 102, 'C');
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
2 VALUES (10000, 'HIS', 101, 'A');
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
2 VALUES (10001, 'HIS', 101, 'B');
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
2 VALUES (10002, 'HIS', 101, 'B');
1 row created.
SQL>
SQL>
SQL> CREATE OR REPLACE FUNCTION CountCredits (
2 p_ID IN lecturer.ID%TYPE)
3 RETURN NUMBER AS
4
5 v_TotalCredits NUMBER; -- Total number of credits
6 v_CourseCredits NUMBER; -- Credits for one course
7 CURSOR c_RegisteredCourses IS
8 SELECT department, course
9 FROM myStudent
10 WHERE student_id = p_ID;
11 BEGIN
12 FOR v_CourseRec IN c_RegisteredCourses LOOP
13 SELECT num_credits
14 INTO v_CourseCredits
15 FROM session
16 WHERE department = v_CourseRec.department
17 AND course = v_CourseRec.course;
18
19 v_TotalCredits := v_TotalCredits + v_CourseCredits;
20 END LOOP;
21
22 RETURN v_TotalCredits;
23 END CountCredits;
24 /
Function created.
SQL>
SQL>
SQL> CREATE TABLE MyTable (
2 num_col NUMBER,
3 char_col VARCHAR2(60)
4 );
Table created.
SQL>
SQL>
SQL>
SQL> CREATE OR REPLACE PROCEDURE CreditLoop AS
2 myLecturerID lecturer.ID%TYPE;
3 v_Credits lecturer.current_credits%TYPE;
4 CURSOR c_lecturer IS
5 SELECT ID
6 FROM lecturer;
7 BEGIN
8 OPEN c_lecturer;
9 LOOP
10 FETCH c_lecturer INTO myLecturerID;
11 v_Credits := CountCredits(myLecturerID);
12 INSERT INTO MyTable (num_col, char_col)
13 VALUES (myLecturerID, 'Credits = ' || TO_CHAR(v_Credits));
14 EXIT WHEN c_lecturer%NOTFOUND;
15 END LOOP;
16 CLOSE c_lecturer;
17 END CreditLoop;
18 /
Procedure created.
SQL>
SQL> drop table MyTable;
Table dropped.
SQL> drop table session;
Table dropped.
SQL> drop table myStudent;
Table dropped.
SQL> drop table lecturer;
Table dropped.
SQL>