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Gate 2008 IT DBMS Relational Please help with this question . Stud...
Gate 2008 IT DBMS Relational
Please help with this question .

Student (school-id, sch-roll-no, sname, saddress)
School (school-id, sch-name, sch-address, sch-phone)
Enrolment(school-id sch-roll-no, erollno, examname)
ExamResult(erollno, examname, marks)

Consider the following tuple relational calculus query.
{t | ∃ E ∈
Enrolment t = E.school-id ∧
| {x | x ∈ Enrolment ^ x.school-id = t ∧

(∃ B ∊ ExamResult B.erollno = x.erollno ∧
B.examname = x.examname ∧

B.marks > 35)}| /

| {x | x ∊ Enrolment ∧

x.school-id = t}| * 100 > 35}
If a student needs to score more than 35 marks to pass an exam, what does the query return?

a The empty set
b schools with more than 35% of its students enrolled in some exam or the other
c schools with a pass percentage above 35% over all exams taken together
d schools with a pass percentage above 35% over each exam

4Comments
Apoorva Jain @apoorvaj1
17 Dec 2018 12:39 pm
@ranita mam plz help
Pritam Prasun @pritam
23 Dec 2018 03:58 pm
Apoorva, Please correct the question. It seems to have many typos.
Rajesh @rajeshrajput1
9 Feb 2019 02:00 pm
b
preeti Saini @preetis
2 Dec 2019 12:10 pm
Nice
GATE-2017-Set-1 | Computer Science and Information Technology
Difficulty Level:  advanced
Total Questions: 0
This Quiz is not available right now.
0Comment
Transaction Management, Files ​:- 1st Dec - 2018

Hi there,

As per the Virtual GATE - '19 Schedule, classroom discussion will be about Memory Management.

Please follow the links below for a better understanding of the said topic and post your Doubts and Queries.

You can also post Examples and Notes to help your Peers.

Transaction Management :- https://www.techtud.com/chapter/transaction-management

Files :- https://www.techtud.com/chapter/files

Quiz :- https://www.techtud.com/quiz/file-structure

0Comment
Process Synchronisation :- 24th Nov - 2018

Hi there,

As per the Virtual GATE - '19 Schedule, classroom discussion will be about Process Synchronisation.

Please follow the links below for a better understanding of the said topic and post your Doubts and Queries.

You can also post Examples and Notes to help your Peers.

Process Synchronisation :-

0Comment
Process Management :- 23th Nov - 2018

Hi there,

As per the Virtual GATE - '19 Schedule, classroom discussion will be about Process Management.

Please follow the links below for a better understanding of the said topic and post your Doubts and Queries.

You can also post Examples and Notes to help your Peers.

  • Process Management :-

Introduction to Operating System:- https://www.techtud.com/chapter/introduction-operating-system

Process Management:- https://www.techtud.com/chapter/process-management

0Comment
ALU, DMA, I/O - 21th Oct, 2018

Hi there,

As per the Virtual GATE - '19 Schedule, today's classroom discussion will be about  ALU, DMA, I/O .

Please follow the links below for a better understanding of the said topic and post your Doubts and Queries.

You can also post Examples and Notes to help your Peers.

0Comment
Maths-2 VirtualGATE is postponed

Hello all,

This is to inform you that the maths-2 test will be delayed for a day. We will announce the status by tomorrow.

Actually, the idea is to move the test from http://virtualgate.in to Techtud itself so that we can involve more into the discussion, bookmark specific question for later revision and most of all attempt the test in GATE environment.

The development team is about to finalize the development and hence we have decided to delay this test a bit. However, you are encouraged to keep preparing at the proper pace.

Trust me, the delay is for the greater good.

Below is what is coming:

1Comment
Abhishek Shaw @abhishekshaw
19 Oct 2018 03:04 pm
@pritam Sir any update ?
Machine instructions and addressing modes - 20th Oct, 2018

Hi there,

As per the Virtual GATE - '19 Schedule, today's classroom discussion will be about  Machine instructions and addressing modes .

Please follow the links below for a better understanding of the said topic and post your Doubts and Queries.

You can also post Examples and Notes to help your Peers.

 

0Comment