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About Question enthuware.oce-jpad.v6.2.490 :

Posted: Sun Jul 16, 2017 7:37 am
by supafly
The explanation to option 4 is wrong. COUNT(), MIN() and MAX() can be used without a GROUP BY clause. But they can only be used in side a select clause.

For example this is valid:

SELECT COUNT(o)
FROM Order o

cheers

Re: About Question enthuware.oce-jpad.v6.2.490 :

Posted: Sun Jul 16, 2017 7:46 pm
by himaiMinh
Hi, Supafly,
Which test and which question no. this question belongs?
But this is not valid:
Select o.id, count(o) from Order o because group by clause does not exist.
When there are more than one path in the select clause with aggregate functions (count, max, min....), the group by clause is needed.

Re: About Question enthuware.oce-jpad.v6.2.490 :

Posted: Sun Jul 16, 2017 10:12 pm
by admin
The explanation doesn't say that you cannot use count without group by at all. It says you cannot mix grouped columns and non-grouped columns without a group by.

This explanation is in context of the option 5:
select s.firstname, count(p) from Student s left join s.presentations p

Here, you cannot mix s.firstname and count(p) without a group by for firstname.

Himai, this is in test 3, q 47. But you can simply open the question by doing control+q and entering 2.490 in ETS Viewer.

HTH,
Paul.

Re: About Question enthuware.oce-jpad.v6.2.490 :

Posted: Mon Jul 17, 2017 12:51 am
by supafly
That is true, i misread the explanation.

Re: About Question enthuware.oce-jpad.v6.2.490 :

Posted: Sat Dec 16, 2017 4:09 am
by dominik.jenik
Looks like logical contradiction. I think answer 1 is also correct. Because we are not having multiple students with same name therefore with or without grouping we get the same result.

Re: About Question enthuware.oce-jpad.v6.2.490 :

Posted: Sat Dec 16, 2017 10:24 pm
by admin
No, it is not contradictory. "First names are unique" implies that no two students have same first name. Duplicate rows in the results will be there if same student makes multiple presentations.

Re: About Question enthuware.oce-jpad.v6.2.490 :

Posted: Sat Sep 01, 2018 9:03 am
by Emmeline
no no man it is not https://athletesphysiques.com/dianabol-review-results/ what you think it is first name is always unique