Mega Code Archive

CASE WHEN statement with variable

SQL> SQL> 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> select * from lecturer; ID FIRST_NAME LAST_NAME MAJOR CURRENT_CREDITS -------- -------------------- -------------------- ------------------------------ --------------- ######## Scott Lawson Computer Science 11.00 ######## Mar Wells History 4.00 ######## Jone Bliss Computer Science 8.00 ######## Man Kyte Economics 8.00 ######## Pat Poll History 4.00 ######## Tim Viper History 4.00 ######## Barbara Blues Economics 7.00 ######## David Large Music 4.00 ######## Chris Elegant Nutrition 8.00 ######## Rose Bond Music 7.00 ######## Rita Johnson Nutrition 8.00 ID FIRST_NAME LAST_NAME MAJOR CURRENT_CREDITS -------- -------------------- -------------------- ------------------------------ --------------- ######## Sharon Clear Computer Science 3.00 12 rows selected. SQL> DECLARE 2 v_Major lecturer.major%TYPE; 3 v_CourseName VARCHAR2(10); 4 BEGIN 5 SELECT major 6 INTO v_Major 7 FROM lecturer 8 WHERE ID = 10011; 9 10 CASE v_Major 11 WHEN 'Computer Science' THEN 12 v_CourseName := 'CS 101'; 13 WHEN 'Economics' THEN 14 v_CourseName :='ECN 203'; 15 WHEN 'History' THEN 16 v_CourseName := 'HIS 101'; 17 WHEN 'Music' THEN 18 v_CourseName := 'MUS 100'; 19 WHEN 'Nutrition' THEN 20 v_CourseName := 'NUT 307'; 21 ELSE 22 v_CourseName := 'Unknown'; 23 END CASE; 24 25 DBMS_OUTPUT.PUT_LINE(v_CourseName); 26 END; 27 / NUT 307 PL/SQL procedure successfully completed. SQL> SQL> drop table lecturer; Table dropped.