What does the term “aggregate functions” refer to-What are the various aggregate operations used in relational operations?

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.