4.
begin
DBMS_OUTPUT.PUT_LINE('HELLO WORLD!');
END;

----


4.

DECLARE
v_myage number:=31;
begin
if v_myage > 11
then
dbms_output.put_line('I am not a child');
end if;
end;

;


7.
DECLARE
v_deptid number;
v_deptname varchar2(20);
v_emps number;
v_mngid number :=108;

begin

case v_mngid
when 108 then
select department_id, department_name
into v_deptid, v_deptname from departments
where manager_id=108;
select count(*) into v_emps from employees
where department_id = v_deptid;
end case;
dbms_output.put_line('pracujesz w departamencie: '|| v_deptname || ' department. Jest tam '|| v_emps || ' pracownikow');
end;


8.
DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=1;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;
loop
insert into locations (location_id, city, country_id)
values ((v_loc_id + v_counter), v_new_city, v_countryid);
v_counter:=v_counter+1;
exit when v_counter>3;
end loop;
commit;
end;


9.
select * from locations;

10.
DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=0;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;
loop
delete from locations where location_id=(v_loc_id - v_counter);
v_counter:=v_counter+1;
exit when v_counter>2;
end loop;
commit;
end;


11.
DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=1;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;
loop
insert into locations (location_id, city, country_id)
values ((v_loc_id + v_counter), v_new_city, v_countryid);
dbms_output.put_line('v counter: '||v_counter||' wartosc nowego loc_id: '||(v_loc_id+v_counter));
v_counter:=v_counter+1;
exit when v_counter>3;
end loop;
commit;
end;

12.
DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=0;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;
loop
delete from locations where location_id=(v_loc_id - v_counter);
v_counter:=v_counter+1;
exit when v_counter>2;
end loop;
commit;
end;

13.
DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=1;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;

while v_counter<3 loop
insert into locations (location_id, city, country_id)
values ((v_loc_id + v_counter), v_new_city, v_countryid);
v_counter:=v_counter+1;
end loop;
commit;
end;

14.
DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=1;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;

while v_counter<=2 loop
delete from locations where
location_id=(v_loc_id - v_counter);
v_counter:=v_counter+1;
end loop;
commit;
end;

select * from locations;

15.
DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=1;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;

for a in 1..3 loop
insert into locations (location_id, city, country_id)
values ((v_loc_id + v_counter), v_new_city, v_countryid);
v_counter:=v_counter+1;
end loop;
commit;
end;

16.

DECLARE
v_countryid locations.country_id%type :='CA';
v_loc_id locations.location_id%type;
v_counter number(2):=1;
v_new_city locations.city%type:='Montreal';

begin
select max(location_id)
into v_loc_id from locations
where country_id=v_countryid;

for a in 1..3 loop
delete from locations where
location_id=(v_loc_id - v_counter);
v_counter:=v_counter+1;
end loop;
commit;
end;

17.