Question-3

DBMS
SQL
Joins

Consider the table below and predict the output of the query that follows.

class house_name no_of_student
Class 9 Aravali 50
Class 10 Nilgiri 40
Class 11 Shiwalik 60
Class 12 Nilgiri 55 
SELECT COUNT(house_name)
FROM ((SELECT class, house_name 
       FROM house_distribution) as X
       NATURAL JOIN (SELECT house_name, no_of_student 
                     FROM house_distribution) as Y);

\(6\)

Given the tables X and Y:

Table X:

class house_name
Class 9 Aravali
Class 10 Nilgiri
Class 11 Shiwalik
Class 12 Nilgiri

Table Y:

house_name no_of_student
Aravali 50
Nilgiri 40
Shiwalik 60
Nilgiri 55

The natural join of X and Y on the house_name attribute results in the following table:

class house_name no_of_student
Class 9 Aravali 50
Class 10 Nilgiri 40
Class 12 Nilgiri 40
Class 11 Shiwalik 60
Class 10 Nilgiri 55
Class 12 Nilgiri 55

Counting the occurrences of house_name in the joined table yields a count of \(6\).