create table emp
(
id int,
name varchar(25),
salary number
);
insert into emp values(18,'Gala',25000);
insert into emp values(17,'Sujal',20000);
insert into emp values(65,'Yash',27000);
insert into emp values(61,'Sahil',30000);
insert into emp values(40,'Aayush',50000);
insert into emp values(23,'Gori',60000);
select * from emp;
select name from emp;
select id,name from emp;
alter table emp add(city varchar(25));
update emp SET city='Mumbai';
select * from emp;
update emp SET city='Ahmedabad' where id=18;
update emp SET city='Surat' where id=61;
select * from emp;
create table emp1 as select * from emp;
truncate table emp;
select * from emp;
ROLLBACK;
select * from emp;
COMMIT;
select * from emp;
drop table emp;
select * from emp;
select * from emp1;
delete from emp1 where id=61;
select * from emp1;
create view empview1 as select id,name from emp1;
select *from empview1;
update emp1 SET city='' where id=23;
select * from emp1;
select *from empview1;
create view empview2 as select id,name from emp1 where city IS NOT NULL;
select *from empview2;
create table stud
(
rollno int,
name varchar(25),
class varchar(10),
primary key(rollno)
);
insert into stud values(1,'Vishal','FYIT');
insert into stud values(2,'Amit','FYDS');
insert into stud values(3,'Deva','FYIT');
insert into stud values(4,'Bhavesh','FYDS');
insert into stud values(5,'Abhay','FYIT');
insert into stud values(6,'Om','FYDS');
insert into stud values(7,'Nikhil','FYIT');
insert into stud values(8,'Shhubham','FYDS');
select *from stud;
create table address
(
rollno int,
zipcode number,
city varchar(25),
foreign key (rollno) references stud(rollno)
);
insert into address values(1,401209,'Mumbai');
insert into address values(2,423209,'Delhi');
insert into address values(3,469209,'Pune');
insert into address values(4,401789,'Jaipur');
insert into address values(8,401789,'Kolkata');
select *from address;
select name,zipcode,city from stud inner join address on stud.rollno=address.rollno;
select stud.rollno,name,city from stud left join address on stud.rollno=address.rollno;
select stud.rollno,class,zipcode from stud right join address on stud.rollno=address.rollno;
select stud.rollno,class,zipcode from stud cross join address;
select name,zipcode,city,stud.rollno from stud,address;
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