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Posted by Andreas Gagnier Ruckert
Andreas Gagnier Ruckert
10,352 Points

Stumped on Grouping, Joining and Cleaning Database Challenge 1.

I keep getting an error message on this challenge, even though it returns a table with the averages down below. My code is: SELECT movie_id, AVG(score) AS average FROM reviews GROUP BY movie_id;

Any help would be appreciated.

Andreas Gagnier Ruckert
Andreas Gagnier Ruckert
10,352 Points

The challenge reads:

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

1 Answer

Ken Alger
STAFF
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

Andreas;

We are given a challenge prompt of: Group all reviews by "movie_id" and get the average "score" and alias it as "average".

Let's take a look, eh?

We need to get (SELECT) the score data and average it (AVG(score)), and call it "average" (AS average). We need to obtain the data from (FROM) a location (table name) and group all of these reviews by "movie_id" (GROUP BY movie_id). If memory serves, this all resides in a table titled reviews so that would be FROM where we select it, correct?

Our code statement then would be:

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

I think you were very close but were also choosing the movie_id field, which is not necessary for this particular task.

Happy coding,

Ken

Andreas Gagnier Ruckert
Andreas Gagnier Ruckert
10,352 Points

Thank you very much, I now see my error. That works better!

John Hebron
John Hebron
23,993 Points
John Hebron
John Hebron
23,993 Points

This was super helpful to me as well. Thank you!