/* performing addition operation on Marks column in student table */
create Table  student1(Name varchar(255),RollNo varchar(255),Marks int);
insert into student1(Name, RollNo ,Marks)values("Ram",1,42);
insert into student1(Name, RollNo ,Marks)values("John",2,43);
insert into student1(Name, RollNo ,Marks)values("Neha",3,45);
select * from student1;
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select Name, Marks+20  from student1;