Mega Code Archive

DELETE statement in PLSQL block

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) 9 ); 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> 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> SQL> select * from session; DEP COURSE --- -------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------- MAX_LECTURER CURRENT_LECTURER NUM_CREDITS ROOM_ID ------------ ---------------- ----------- -------- HIS 101.00 History 101 30.00 11.00 4.00 ######## HIS 301.00 History 301 30.00 .00 4.00 ######## DEP COURSE --- -------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------- MAX_LECTURER CURRENT_LECTURER NUM_CREDITS ROOM_ID ------------ ---------------- ----------- -------- CS 101.00 Computer Science 101 50.00 .00 4.00 ######## ECN 203.00 Economics 203 DEP COURSE --- -------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------- MAX_LECTURER CURRENT_LECTURER NUM_CREDITS ROOM_ID ------------ ---------------- ----------- -------- 15.00 .00 3.00 ######## CS 102.00 Computer Science 102 35.00 3.00 4.00 ######## MUS 410.00 DEP COURSE --- -------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------- MAX_LECTURER CURRENT_LECTURER NUM_CREDITS ROOM_ID ------------ ---------------- ----------- -------- Music 410 5.00 4.00 3.00 ######## ECN 101.00 Economics 101 50.00 .00 4.00 ######## DEP COURSE --- -------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------- MAX_LECTURER CURRENT_LECTURER NUM_CREDITS ROOM_ID ------------ ---------------- ----------- -------- NUT 307.00 Nutrition 307 20.00 2.00 4.00 ######## MUS 100.00 Music 100 100.00 .00 3.00 DEP COURSE --- -------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------- MAX_LECTURER CURRENT_LECTURER NUM_CREDITS ROOM_ID ------------ ---------------- ----------- -------- 9 rows selected. SQL> SQL> DECLARE 2 myLecturerCutoff NUMBER; 3 BEGIN 4 myLecturerCutoff := 10; 5 DELETE FROM session 6 WHERE current_lecturer < myLecturerCutoff; 7 8 DELETE FROM lecturer 9 WHERE current_credits = 0 10 AND major = 'Economics'; 11 END; 12 / PL/SQL procedure successfully completed. 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> SQL> select * from session; DEP COURSE --- -------- DESCRIPTION -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------- MAX_LECTURER CURRENT_LECTURER NUM_CREDITS ROOM_ID ------------ ---------------- ----------- -------- HIS 101.00 History 101 30.00 11.00 4.00 ######## SQL> SQL> drop table lecturer; Table dropped. SQL> SQL> drop table session; Table dropped. SQL> SQL> SQL>