DELETE statement in PL/SQL 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>