Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

PHP

Posted by Mike Smith
Mike Smith
11,863 Points

Issues with grouping-joining-and-cleaning-up Quiz section

Okay,

I'm in the grouping-joining-and-cleaning-up Quiz section and it is asking for :

"Like before, group reviews by "movie_id", get the average "score" as "average" and filter out any averages over 2."

I respond with SQL of:

""SELECT movie_id, avg(score) as average from reviews group by movie_id having average > 2;"

and the results are :

movie_id average 2 0.30732E1 3 0.38333E1 4 0.27E1 5 0.36154E1 8 0.29167E1

It works in MySQL Workbench just fine, but you cannot go forward in the quiz with incorrect results.

Any suggestions? What am I missing?

Mike

4 Answers

Ben Rubin
PLUS
Ben Rubin
Courses Plus Student 14,658 Points
Ben Rubin
Ben Rubin
Courses Plus Student 14,658 Points

"Filter out any averages over 2" means that you don't want the averages over two. It's a little confusing in the wording. Just flip your > sign and you've got it.

Mike Smith
Mike Smith
11,863 Points
Mike Smith
Mike Smith
11,863 Points

Thank-you Ben. I did catch that after I sent the forum question. But even after correcting that issue, the results are still returning averages less than 1. If I run the same SQL against the DB in Workbench, it returns valid information, just not in the quiz application.

Vernon Watson
Vernon Watson
8,854 Points
Vernon Watson
Vernon Watson
8,854 Points 
SELECT movies.title, IFNULL(AVG(score),0) AS average 
FROM reviews RIGHT OUTER JOIN movies 
ON movies.id = reviews.movie_id 
GROUP BY movie_id HAVING average < 2;

That was a tough one!

Jonathan Fauteux
Jonathan Fauteux
6,823 Points
Jonathan Fauteux
Jonathan Fauteux
6,823 Points

for the first part of the exercise, there seems to be a lack of information.

The question is :

Group all reviews by "movie_id" and get the average "score" and alias it as "average".

I am using:

SELECT movie_id, AVG(score) AS average FROM reviews GROUP BY movie_id;

It dosen't work? any idea?