php - Database Design for students marks per paper -


earlier i've asked question attendance system. in same system, i'm having separate table store students marks. now, before question show i've done far:

in every semester there 2 papers. there 6 semesters complete course. in first paper student can have maximum marks of 75 , second paper marks of 25. now, i've build simple table students_marks follows: 

name        | type  ------------|------- marks_id    | int s_id        | int sem_id      | int sessionyear | varchar(11) paper_one   | decimal(11,0) paper_two   | decimal(11,0)

now, marks_id primary key, while s_id , sem_id foreign keys 2 other tables student_info , semester.

to output marks obtained this:

select * `student_marks`  join `student_info` on student_marks.s_id = student_info.s_id  student_info.deleted = ?  , `sem_id` = ? , `sessionyear` = ? order `class_roll`

what didn't realize on 5th , 6th semester there 4 papers each paper maximum marks of 50. if add 2 more column above table redundant other semesters wont need have 4 papers.

i'm looking re-design table enable me incorporate new papers.

thanks in advance.

note: i'm using mysql database , php creating application.

i use more normalised form:

create table student (id int, -- pk 1                       studentinfo ... )-- student info  create table attendance (studentid int, -- fk student                          semesterid int)   create table paper (studentid int, --fk student table                     selemsterid int, -- fk attendance table                     paperid int, -- 1 each paper                     paperdate date, -- allows retakes                     papermark decimal(11,0) ) -- store marks  select s.*, p.* student s inner join attendance on a.studentid = s.id inner join paper p on p.studentid = s.id , p.semesterid = s.semesterid

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