Assignment 1
Question One
a) What is natural join operation in relational algebra and why do we need it.
(b) From the below given tables:
Student
| SID | Name | Grade | Dept-ID |
| 1 | Abdullah | 95 | CS |
| 2 | Naif | 94 | IT |
| 3 | Rayan | 92 | DS |
| 4 | Suleman | 93 | DS |
Enrolled Department
| Dept-ID | Department |
| CS | Computer Science |
| IT
DS |
Information Technology
Data Science |
Write a relational algebra query to find the names of all students in relation to the departments in which they are enrolled.
Show the results of the natural join operation from the part (i) query in a table.
Question Two
What does the term “aggregate functions” refer to? What are the various aggregate operations used in relational operations?
| 2 Marks |
| Learning Outcome(s):
Recognize database file organization and indexing. |
Question Three
Create B-tree of degree 3 for the following set of key values added in order. Show the steps after every insertion.
43, 24, 33, 60, 20, 22, 51, 32, 27
| 2 Marks |
| Learning Outcome(s):
Recognize database file organization and indexing. |
Question Four
What type of method for collision resolution is shown below? briefly explain it by your own words.
Define another type of method for collision resolution and provide example.
