Oracle 18c

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CREATE TABLE grades (STUDNETID INTEGER,
                     SECTIONID INTEGER,
                     SECTIONINFO VARCHAR2(10),
                     COURSEID INTEGER,
                     COURSENAME VARCHAR2(50),
                     GRADE VARCHAR2(1));
CREATE OR REPLACE TRIGGER grade_trigger
  BEFORE INSERT OR UPDATE ON grades
  FOR EACH ROW
BEGIN
  IF substr(upper(:new.coursename), -1) IN ('A', 'B', 'C', 'D', 'E', 'F')
  THEN
    :new.grade := 'A';
  ELSIF substr(upper(:new.coursename), -1) IN ('G', 'H', 'I', 'J', 'K')
  THEN
    :new.grade := 'B';
  ELSIF substr(upper(:new.coursename), -1) IN ('L', 'M', 'N', 'O', 'P')
  THEN
    :new.grade := 'C';
  ELSIF substr(upper(:new.coursename), -1) IN ('Q', 'R', 'S', 'T')
  THEN
    :new.grade := 'D';
  ELSIF substr(upper(:new.coursename), -1) IN ('U', 'V', 'W', 'X', 'Y', 'Z')
  THEN
    :new.grade := 'E';
  END IF;
END grade_trigger;
/
INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (234501,153, '078',256877 , 'Intro to Holographic',null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (234519,153, '078',256877 ,'Intro to Holographic', null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME ,GRADE) VALUES (234505,153, '078',256877 ,'Intro to Holographic', null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (23405,21, '012A',23532 ,'Starfleet Intro', null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (23419,21, '012A',23532 ,'Starfleet Intro', null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (23401,21, '012A',23532 ,'Starfleet Intro', null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (23418,21, '012A',23532 ,'Starfleet Intro', null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (234520,933,'278',843234 ,'Borg Technolgy', null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (234505,933,'278',843234 ,'Borg Technolgy' ,null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID,COURSENAME, GRADE) VALUES (234501,933,'278',843234 ,'Borg Technolgy' ,null);
1 rows affected

INSERT INTO GRADES (STUDNETID, SECTIONID, SECTIONINFO, COURSEID, COURSENAME,GRADE) VALUES (234519,438,'531',542303 , 'Intro to Genetics',null);
1 rows affected

commit;
select * from grades;


STUDNETID
SECTIONID
SECTIONINFO
COURSEID
COURSENAME
GRADE


234501
153
078
256877
Intro to Holographic
A

234519
153
078
256877
Intro to Holographic
A

234505
153
078
256877
Intro to Holographic
A

23405
21
012A
23532
Starfleet Intro
C

23419
21
012A
23532
Starfleet Intro
C

23401
21
012A
23532
Starfleet Intro
C

23418
21
012A
23532
Starfleet Intro
C

234520
933
278
843234
Borg Technolgy
E

234505
933
278
843234
Borg Technolgy
E

234501
933
278
843234
Borg Technolgy
E

234519
438
531
542303
Intro to Genetics
D

STUDNETID	SECTIONID	SECTIONINFO	COURSEID	COURSENAME	GRADE
234501	153	078	256877	Intro to Holographic	A
234519	153	078	256877	Intro to Holographic	A
234505	153	078	256877	Intro to Holographic	A
23405	21	012A	23532	Starfleet Intro	C
23419	21	012A	23532	Starfleet Intro	C
23401	21	012A	23532	Starfleet Intro	C
23418	21	012A	23532	Starfleet Intro	C
234520	933	278	843234	Borg Technolgy	E
234505	933	278	843234	Borg Technolgy	E
234501	933	278	843234	Borg Technolgy	E
234519	438	531	542303	Intro to Genetics	D