SQL: Database structure -


i have little blackout.

in database have til following tables:

  • courses: id
  • students: id
  • coursesstudents: courseid, studentid

now have problems connecting marks students , courses.

the marks must connected school year. e. g.

  • 1st year, 1st semester : 12 points
  • 1st year, 2nd semester: 10 points
  • 2nd year, 1st semester: 8 points
  • 2nd year, 2nd semester: 5 points

i thought 

studentscoursesmarksyear: studentid, coursesid, mark, year

but think not right/the best...

you're close. year doesn't sufficient; need semester, too.

studentmarks: studentid, courseid, mark, year, semester

primary key {studentid, courseid, mark, year, semester}. since it's key, it's in bcnf @ least.

in real-world academic application, you'd need several other tables. one, example, might have years , semesters particular course offered. (some of courses offered in even-numbered years.)


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