Generating Data for INSERT using a Stored Procedure, Function and Cursor

Question

I've written a function that I finally got to compile, but was not successful in importing and inserting the data needed to populate a table with at least 1800 rows. Here's what I needed to do:
-- Generate a random test score ranging from 20 to 100 (already done)
-- Generate a random final grade for the course ranging from 4 to 0 (representing A to F) (already done, but question below.
-- Use conditional statements based on the counter to assign three courses (already done -- see SQL statements)
-- Process no more than 95% of the students (300) for test 1.
-- For test 2, process no more than 80% of the students who took test 1. Student cannot take test 2 unless the student takes test 1 (does this require a trigger? If so, how would I go about doing this?)
-- Use a function or another subprocedure to process the grade using IF-ELSIF statements
For example, I've tried the following statements:
For procedures
IF birth_date BETWEEN to_date('01-Jan-89 AND to_date('31-Dec-89','dd-Mon-yy') THEN
school_grade := 6;
AND for functions:
IF birth_date BETWEEN to_date('01-Jan-89 AND to_date('31-Dec-89','dd-Mon-yy') THEN
RETURN (6);
RETURN;
- or -
IF birth_date BETWEEN to_date('01-Jan-89','dd-Mon-yy') AND to_date('31-Dec-89','dd-Mon-yy') THEN
school_grade := 9
RETURN school_grade;
-- Read the birth_date into the main procedure so that the value returned from the subprocedure or function can populate the birth_date column.
To give you an idea of what I've already done:
SQL>
SQL> CREATE OR REPLACE PROCEDURE add_tests (v_school_grade IN NUMBER) AS
2
3 v_counter NUMBER(3) := 0;
4 v_num_students CONSTANT NUMBER(3) := 300;
5 v_students_test1 NUMBER := 0;
6 v_students_test2 NUMBER := 0;
7 v_student_id VARCHAR2(5);
8 v_course1 VARCHAR2(2);
9 v_course2 VARCHAR2(2);
10 v_course3 VARCHAR2(2);
11 v_course4 VARCHAR2(2);
12 v_student_grade NUMBER(1) := 0;
13 v_test_score NUMBER(3) := 0;
14 v_course_final_grade NUMBER(1) := 0;
15 v_birth_date DATE;
16
17 FUNCTION pkg_get_grade RETURN NUMBER
18 IS
19
20 v_birth_date DATE;
21 v_school_grade NUMBER(1) :=0;
22
23 CURSOR grade_cur IS
24 SELECT birth_date FROM students;
25
26 BEGIN
27 OPEN grade_cur;
28 LOOP
29 FETCH grade_cur INTO v_birth_date;
30
31 EXIT WHEN grade_cur%NOTFOUND;
32
33 -- Assign student grade
34
35 -- 9th Grade
36
37 IF v_birth_date < TO_DATE('01-Jan-87','DD-Mon-YY') THEN
38 v_school_grade := 9;
39
40 -- 8th grade
41
42 ELSIF v_birth_date BETWEEN
43 TO_DATE('01-Jan-87','DD-Mon-YY') AND
44 TO_DATE('31-Dec-87','DD-Mon-YY') THEN
45
46 v_school_grade := 8;
47
48 -- 7th grade
49
50 ELSIF v_birth_date BETWEEN
51 TO_DATE('01-Jan-88','DD-Mon-YY') AND
52 TO_DATE('31-Dec-88','DD-Mon-YY') THEN
53
54 v_school_grade := 7;
55
56 -- 6th grade
57
58 ELSIF v_birth_date BETWEEN
59 TO_DATE('01-Jan-89','DD-Mon-YY') AND
60 TO_DATE('31-Dec-89','DD-Mon-YY') THEN
61
62 v_school_grade := 6;
63
64 -- 5th grade
65
66 ELSIF v_birth_date > TO_DATE('31-Dec-89','DD-Mon-YY') THEN
67
68 v_school_grade := 5;
69
70 END IF; -- end if loop for student's grade
71 END LOOP; -- end loop for grade_cur
72 CLOSE grade_cur; -- close cursor for assigning grade
73 RETURN v_school_grade;
74
75 END pkg_get_grade;
76
77 PROCEDURE delete_test_info AS
78
79 BEGIN
80
81 DELETE FROM student_facts;
82
83 END delete_test_info;
84
85 BEGIN
86
87 -- Process student for tests
88
89 WHILE (v_counter <= v_num_students) LOOP
90 v_counter := v_counter + 1; -- initialize counter
91
92 -- Set student id
93
94 v_student_id := 'S'&#0124; &#0124;v_counter;
95
96 -- portion of students taking beginning of year tests
97
98 v_students_test1 := v_num_students * .95;
99
100
101 -- Portion of students taking end of year tests
102
103 v_students_test2 := v_students_test1 * .80;
104
105
106 -- Est. test scores between 20 and 100
107
108 v_test_score := random.rand_max(80) + 20;
109
110
111 -- Est. final grade for course between 0 and 4
112
113 v_course_final_grade := random.rand_max(4);
114
115
116 -- Process tests for courses
117
118 IF v_counter < ROUND(v_num_students * .20) THEN
119 v_course1 := 'C1';
120 v_course2 := 'C2';
121 v_course3 := 'C3';
122
123 ELSIF v_counter BETWEEN ROUND(v_num_students * .20)
124 AND ROUND(v_num_students * .40) THEN
125
126 v_course1 := 'C2';
127 v_course2 := 'C1';
128 v_course3 := 'C3';
129
130 ELSE IF v_counter BETWEEN ROUND(v_num_students * .40)
131 AND ROUND(v_num_students * .60) THEN
132
133 v_course1 := 'C3';
134 v_course2 := 'C1';
135 v_course3 := 'C2';
136
137 ELSE IF v_counter BETWEEN (v_num_students * .60)
138 AND ROUND(v_num_students * .80) THEN
139
140 v_course1 := 'C3';
141 v_course2 := 'C1';
142 v_course3 := 'C2';
143
144 ELSE
145 v_course1 := 'C4';
146 v_course2 := 'C2';
147 v_course3 := 'C3';
148
149 END IF;
150 END IF;
151 END IF;
152
153 -- Input test information for students
154
155 -- Beginning of year test for Course 1
156
157 IF v_counter <= v_students_test1 THEN
158 INSERT INTO studentfacts
159 VALUES(v_student_id, v_course1, 'ACH1999',
160 TO_DATE('01-SEP-1999','DD-MON-YYYY'),
161 v_student_grade, v_course_final_grade, v_test_score);
162 ELSE
163 INSERT INTO studentfacts
164 VALUES(v_student_id, v_course1, 'ACH1999',
165 TO_DATE('01-SEP-1999','DD-MON-YYYY'),
166 v_student_grade, v_course_final_grade, NULL);
167 END IF;
168
169
170 -- End of year test for Course 1
171
172 IF v_counter <= v_students_test2 THEN
173 INSERT INTO studentfacts
174 VALUES(v_student_id, v_course1,'ACH2000',
175 TO_DATE('01-JUN-2001','DD-MON-YYYY'),
176 v_student_grade, v_course_final_grade, v_test_score);
177 ELSE
178 INSERT INTO studentfacts
179 VALUES(v_student_id, v_course1, 'ACH2000',
180 TO_DATE('01-JUN-2001','DD-MON-YYYY'),
181 v_student_grade, v_course_final_grade, NULL);
182 END IF;
183
184
185 -- Beginning of year test for Course 2
186
187 IF v_counter <= v_students_test1 THEN
188 INSERT INTO studentfacts
189 VALUES(v_student_id, v_course2, 'ACH1999',
190 TO_DATE('01-SEP-1999','DD-MON-YYYY'),
191 v_student_grade, v_course_final_grade,
192 v_test_score);
193 ELSE
194 INSERT INTO studentfacts
195 VALUES(v_student_id, v_course2, 'ACH1999',
196 TO_DATE('01-SEP-1999','DD-MON-YYYY'),
197 v_student_grade, v_course_final_grade, NULL);
198 END IF;
199
200
201 -- End of year test for Course 2
202
203 IF v_counter <= v_students_test2 THEN
204 INSERT INTO studentfacts
205 VALUES(v_student_id, v_course2,'ACH2000',
206 TO_DATE('01-JUN-2001''DD-MON-YYYY'),
207 v_student_grade, v_course_final_grade,
208 v_test_score);
209 ELSE
210 INSERT INTO studentfacts
211 VALUES(v_student_id, v_course2, 'ACH2000',
212 TO_DATE('01-JUN-2001','DD-MON-YYYY'),
213 v_student_grade, v_course_final_grade, NULL);
214 END IF;
215
216
217 -- Beginning of year test for Course 3
218
219 IF v_counter <= v_students_test1 THEN
220 INSERT INTO studentfacts
221 VALUES(v_student_id, v_course3, 'ACH1999',
222 TO_DATE('01-SEP-1999','DD-MON-YYYY'),
223 v_student_grade, v_course_final_grade,
224 v_test_score);
225 ELSE
226 INSERT INTO studentfacts
227 VALUES(v_student_id, v_course3, 'ACH1999',
228 TO_DATE('01-SEP-1999','DD-MON-YYYY'),
229 v_student_grade, v_course_final_grade, NULL);
230 END IF;
231
232
233 -- End of year test for Course 3
234
235 IF v_counter <= v_students_test2 THEN
236 INSERT INTO studentfacts
237 VALUES(v_student_id, v_course3,'ACH2000',
238 TO_DATE('01-JUN-2001','DD-MON-YYYY'),
239 v_student_grade, v_course_final_grade,
240 v_test_score);
241 ELSE
242 INSERT INTO studentfacts
243 VALUES(v_student_id, v_course3, 'ACH2000',
244 TO_DATE('01-JUN-2001','DD-MON-YYYY'),
245 v_student_grade, v_course_final_grade, NULL);
246 END IF;
247
248
249 -- Beginning of year test for Course 4
250
251 IF v_counter <= v_students_test1 THEN
252 INSERT INTO studentfacts
253 VALUES(v_student_id, v_course4, 'ACH1999',
254 TO_DATE('01-SEP-1999','DD-MON-Y YYY'),
255 v_student_grade, v_course_final_grade,
256 v_test_score);
257 ELSE
258 INSERT INTO studentfacts
259 VALUES(v_student_id, v_course4, 'ACH1999',
260 TO_DATE('01-SEP-1999','DD-MON-YYYY'),
261 v_student_grade, v_course_final_grade, NULL);
262 END IF;
263
264
265 -- End of year test for Course 4
266
267 IF v_counter <= v_students_test2 THEN
268 INSERT INTO studentfacts
269 VALUES(v_student_id, v_course4,'ACH2000',
270 TO_DATE('01-JUN-2001', 'DD-MON-YYYY'),
271 v_student_grade, v_course_final_grade, v_test_score);
272 ELSE
273 INSERT INTO studentfacts
274 VALUES(v_student_id, v_course4, 'ACH2000',
275 TO_DATE('01-JUN-2001','DD-MON-YYYY'),
276 v_student_grade, v_course_final_grade, NULL);
277
278 END IF;
279 END LOOP;
280 END add_tests;
281 /
Procedure created.
SQL>
SQL> show errors
No errors.
SQL>
SQL> Input truncated to 9 characters
spool off
When I executed the main procedure, no data populated the student_table. I've tried several things, but I was not still able to populate the student_fact table (I've been at this for more than a week now, but haven't figured a way to populate the student_facts table with at least 1800 rows). Can you tell me what I need to change (if anything) whether if I need to structure things differently? I'm thinking that I missed something in calling the birth_date into the main procedure or returning the value from either a function or subprocedure. Related to the random final grade -- is there a way to sum the totals of the test scores (each student will have three), and generate a final grade from these values.
I also compiled successfully a package containing this same information, but don't know how to execute it to see whether this approach works.
Many thanks to anyone who can help.
null

Answer 1

ldsw,
I am not sure if I totally understand everything that you are trying to do, but I tried to clean up your code and what is listed below is what I came up with. Please see if you can make use of any of it.
SQL> EDIT ldsw
CREATE OR REPLACE PACKAGE ldsw
AS
CURSOR grade_cur
IS
SELECT birth_date
FROM students;
PROCEDURE delete_test_info;
FUNCTION get_grade
(v_birth_date IN DATE)
RETURN NUMBER;
PRAGMA RESTRICT_REFERENCES (get_grade, WNDS, WNPS, RNDS, RNPS);
PROCEDURE add_tests;
END ldsw;
CREATE OR REPLACE PACKAGE BODY ldsw
AS
v_student_grade NUMBER (1) := 0;
PROCEDURE delete_test_info
IS
BEGIN
DELETE FROM studentfacts;
END delete_test_info;
FUNCTION get_grade
(v_birth_date IN DATE)
RETURN NUMBER
IS
v_school_grade NUMBER (1) := 0;
BEGIN
IF v_birth_date < TO_DATE ('01-Jan-1987', 'DD-Mon-YYYY')
THEN
v_school_grade := 9;
ELSIF v_birth_date BETWEEN TO_DATE ('01-Jan-1987', 'DD-Mon-YYYY') AND TO_DATE ('31-Dec-1987', 'DD-Mon-YYYY')
THEN
v_school_grade := 8;
ELSIF v_birth_date BETWEEN TO_DATE ('01-Jan-1988', 'DD-Mon-YYYY') AND TO_DATE ('31-Dec-1988', 'DD-Mon-YYYY')
THEN
v_school_grade := 7;
ELSIF v_birth_date BETWEEN TO_DATE ('01-Jan-1989', 'DD-Mon-YYYY') AND TO_DATE ('31-Dec-1989', 'DD-Mon-YYYY')
THEN
v_school_grade := 6;
ELSIF v_birth_date > TO_DATE ('31-Dec-1989', 'DD-Mon-YYYY')
THEN
v_school_grade := 5;
END IF;
RETURN v_school_grade;
END get_grade;
PROCEDURE add_tests
IS
v_num_students CONSTANT NUMBER (3) := 300;
v_students_test1 NUMBER := 0;
v_students_test2 NUMBER := 0;
v_counter NUMBER (3) := 0;
v_student_id VARCHAR2 (5);
v_test_score NUMBER (3) := 0;
v_course_final_grade NUMBER (1) := 0;
v_course1 VARCHAR2 (2) := NULL;
v_course2 VARCHAR2 (2) := NULL;
v_course3 VARCHAR2 (2) := NULL;
v_course4 VARCHAR2 (2) := NULL;
BEGIN
ldsw.delete_test_info;
v_students_test1 := v_num_students * .95;
v_students_test2 := v_students_test1 * .80;
FOR rec IN grade_cur
LOOP
v_counter := v_counter + 1;
IF v_counter <= v_num_students
THEN
v_student_id := 'S' &#0124; &#0124; TO_CHAR (v_counter);
v_test_score := random.rand_max (80) + 20;
v_course_final_grade := random.rand_max (4);
IF v_counter < ROUND (v_num_students * .20)
THEN
v_course1 := 'C1';
v_course2 := 'C2';
v_course3 := 'C3';
ELSIF v_counter BETWEEN ROUND (v_num_students * .20) AND ROUND (v_num_students * .40)
THEN
v_course1 := 'C2';
v_course2 := 'C1';
v_course3 := 'C3';
ELSIF v_counter BETWEEN ROUND (v_num_students * .40) AND ROUND (v_num_students * .60)
THEN
v_course1 := 'C3';
v_course2 := 'C1';
v_course3 := 'C2';
ELSIF v_counter BETWEEN ROUND (v_num_students * .60) AND ROUND (v_num_students * .80)
THEN
v_course1 := 'C3';
v_course2 := 'C1';
v_course3 := 'C2';
ELSE
v_course1 := 'C4';
v_course2 := 'C2';
v_course3 := 'C3';
END IF;
SELECT ldsw.get_grade (rec.birth_date)
INTO v_student_grade
FROM DUAL;
IF v_counter <= v_students_test1
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course1,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course1,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
IF v_counter <= v_students_test2
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course1,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course1,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
IF v_counter <= v_students_test1
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course2,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course2,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
IF v_counter <= v_students_test2
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course2,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course2,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
IF v_counter <= v_students_test1
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course3,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course3,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
IF v_counter <= v_students_test2
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course3,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course3,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
IF v_counter <= v_students_test1
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course4,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course4,
'ACH1999',
TO_DATE ('01-SEP-1999', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
IF v_counter <= v_students_test2
THEN
INSERT INTO studentfacts
VALUES (v_student_id,
v_course4,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
v_test_score);
ELSE
INSERT INTO studentfacts
VALUES (v_student_id,
v_course4,
'ACH2000',
TO_DATE ('01-JUN-2001', 'DD-MON-YYYY'),
v_student_grade,
v_course_final_grade,
NULL);
END IF;
END IF;
END LOOP;
END add_tests;
END ldsw;
Save the file.
SQL> START ldsw
Package created.
Package body created.
SQL> EXECUTE ldsw.add_tests
PL/SQL procedure successfully completed.
SQL> SELECT * FROM student_facts;
null