CREATE DATABASE evaluation
CREATE TABLE student(
    ID int,
    Name varchar(20),
    Age int,
    Blood_Group varchar(10),
    Department_name varchar(10),
    Mobile_number int(11)
    );
INSERT INTO student VALUES(1,'Tamim',23,'A+ve','CSE',01412345678);
INSERT INTO student VALUES(2,'Kayes',22,'B-ve','EEE',01912345679);
INSERT INTO student VALUES(3,'Mominul',20,'AB+ve','MSE',01912345680);
INSERT INTO student VALUES(4,'Sakib',24,'O+ve','CSE',01912345618);
INSERT INTO student VALUES(5,'Tamim',24,'O+ve','CSE',01912345682);

CREATE TABLE grades(
    student_id int,
  GPA float,
   Semester varchar(10)
      );

INSERT INTO grades VALUES(1,3.75,'SUMMER');
INSERT INTO grades VALUES(1,2.75,'WINTER');
INSERT INTO grades VALUES(2,3.30,'SUMMER');
INSERT INTO grades VALUES(3,3.60,'SUMMER');
INSERT INTO grades VALUES(2,3.96,'WINTER');
INSERT INTO grades VALUES(4,4.00,'SUMMER');
INSERT INTO grades VALUES(5,2.99,'WINTER');

ALTER TABLE student
ADD CONSTRAINT P_K PRIMARY KEY(ID)

SELECT * FROM student

UPDATE student
SET Mobile_number=01912345678
WHERE Name='Tamim'

INSERT INTO grades VALUES(5,2.45,'SUMMER');


No we cant assign student_id as a primary key of the grades table beacuse its contains same id.