CREATE TABLE Department (
dept_id int primary key,
dept_name varchar(10) not null
);
CREATE TABLE Student (
student_id int primary key,student_name varchar(25),age int, marks int, dept_id int, foreign key(dept_id)
references Department(dept_id));
insert into Department values (1,"Cs"),(2,"Mech"),(3,"Business");
INSERT INTO Student VALUES (101, "Alice",25,85,1),(102,"Bob",21,75,2),(103,"Charlie",22,95,1),
(104,"Diana",20,65,3),(105,"Eva",23,70,2);
select * from Department;
select * from Student;
select dept_name,count(*),avg(marks),max(marks) from Department join Student on Department.dept_id=Student.dept_id group by dept_name
create table log(s_id int , oldm int , newm int , change_date timestamjp default current_timestamp);
create or replace trigger after_up after update on Student for each row
begin
insert into log(s_id,oldm,newm,new)
values(:old.s_id,old.:marks,:new.marks);
END;
/
update Student set marks=88 where student_id=103;
select * from log;
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