Gate2019 cs Q61

61A relational database contains two tables Student and Performance as shown below:

Roll_no.	Student_name
1	Amit
2	Priya
3	Vinit
4	Rohan
5	Smita

Roll_no	Subject_code	Marks
1	A	86
1	B	95
1	C	90
2	A	89
2	C	92
3	C	80

The primary key of the Student table is Roll_no. For the Performance table, the columns Roll_no. and Subject_code together form the primary key. Consider the SQL query given below:
SELECT S.Student_name, sum(P.Marks)
FROM Student S, Performance P
WHERE P.Marks > 84
GROUP BY S.Student_name;
The number of rows returned by the above SQL query is ________.

Note – Numerical Type question

Option : B
Explanation :

Total 5 different student names all 5 group records in result. (In where condition no condition over Roll_no so query produces all groups.)

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