Example 2 - Data Complexity VS. Expression Complexity
Given: Students database for all universities in Israel: Technion, Haifa U, Bar-Ilan U, Tel-Aviv U, Jerusaelm U, Ben-Gurion U.
Data complexity:
Return all students' last name for every university.
Complexity O(n) - n stands for the number of student per university.
Expression complexity:
Return all students' last name.
Complexity O(m) - m stands for number of Technion students.
Return average number of courses for a Technion's student.
Complexity O(m*k) - m stands for number of Technion students and k stands for number of courses per student at the Technion.