Nettuts+ Quiz #11: Do You Know SQL?

92.86%, I think the 9th question is kinda vague, but it’s ok.

Question 9 is wrong, you can use where with aggregate functions:

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Enrico.

I agree with Mauro and Enrico. #9 is wrong. The statement is false.

I use where clauses all the time with aggregate functions.

For example, I just ran this on MS’s “pubs” sample database:

select MAX(discount) from dbo.discounts where discount < 10.5

and it worked just fine (returned answer of 6.70)

crap!! going back to the books to go over SQL. I have to say the app used for the Quiz is too freaking AWESOME!! way to go.

yai, got number 9 right.

Good question but not to right time to learn these . timing problem

100%!!! Woohoo!!!! :-P

it is simply quiz

71,43% !!!!!!! NOT Bad :)

It says WHERE with an aggregate function, not SELECT. For example

You can’t use:
SELECT * FROM salaries
WHERE SUM(salary) > 10000

You need to use:

SELECT * FROM salaries
GROUP BY salary
HAVING SUM(salary) > 10000

The WHERE clause can not be used in conjunction with aggregate functions. Is this statement true or false?

There is no function SUM_WHERE or something like that. I needed this. We can use where later,

SELECT SUM(ID) FROM table
WHERE id > 50

This will work.

But how will work:

SELECT SUM(ID) AS more_50, SUM(ID) AS more_40
FROM table
WHERE id > 50

This will still take the ids where more than 50, but I need more than 40. So I answered this question that we cannot use agg functions with where. Its partially true and partially false.

Only solution I know to get sums of both more_50 and more_40 is to use CASE statement.

great

I got 71.43%