Student-Grade

CREATE TABLE STUDENT(Rollno NUMBER,
                     Name VARCHAR(30),
                     Mark1 NUMBER,
                     Mark2 NUMBER,
                     Mark3 NUMBER,
                     Mark4 NUMBER,
                     Mark5 NUMBER);
INSERT INTO STUDENT VALUES(1,'Abinaya',95,87,98,100,94);
INSERT INTO STUDENT VALUES(6,'Sam',79,53,66,45,60);
INSERT INTO STUDENT VALUES(17,'Deepti',94,63,75,75,89);
INSERT INTO STUDENT VALUES(39,'Raj',30,45,29,57,33);
INSERT INTO STUDENT VALUES(10,'Akash',90,80,90,88,67);
alter table STUDENT add Total NUMBER;
update STUDENT SET Total=Mark1+Mark2+Mark3+Mark4+Mark5;
alter table STUDENT add Average NUMBER;
update STUDENT SET Average=Total/5;
alter table STUDENT add Grade Varchar(30);
update STUDENT set Grade='A' where Average>=90;
update STUDENT set Grade='B' where Average>=80 and Average<90;
update STUDENT set Grade='C' where Average>=70 and Average<80;
update STUDENT set Grade='D' where Average>=60 and Average<70;
update STUDENT set Grade='E' where Average>=50 and Average<60;
update STUDENT set Grade='FAIL' where Average<50;

select * from STUDENT;
select * from STUDENT where Name like 'A%';
select Rollno,Name,Average from STUDENT where Average=(select max(Average) from STUDENT);
select * from STUDENT where Average between 80 and 90;
select * from STUDENT where Name like '_a%';
select * from STUDENT order by Average desc;