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8,273 Points

I thought you couldn't use a WHERE clause when using the SUM keyword?

The challenge is:

We're in a movie database. There's a reviews table with the columns of id, movie_id, username, review and rating. The movie "Starman" has the id of 6. Movie ids are found in the movie_id column in the reviews table. Write a query that totals up all ratings for the movie "Starman" in the reviews table. Alias it as starman_total_ratings.

My query:

SELECT SUM(review) AS "starman_total_ratings" FROM reviews GROUP BY movie_id HAVING movie_id = 6;

I get the error: You're missing the WHERE clause. However I thought that you COULDN'T use a WHERE clause with a SUM keyword and that was the whole point of using the HAVING keyword. Plus, when I try to replace the HAVING keyword with WHERE, it also returns an error.

4 Answers


Try this. If you want to use Where, the Where clause needs to come before group by.

SELECT SUM(review) AS "starman_total_ratings" 
WHERE movie_id = 6
GROUP BY movie_id;

Hope this answers this question

8,273 Points

Thanks for the response. When I tried your query I got back "Your query didn't perform the correct sum calculation."

Hi guys,

The correct code is the following:

SELECT SUM(rating) AS "starman_total_ratings" FROM reviews WHERE movie_id = 6 GROUP BY movie_id;

It was one little mistake. Only the review must be replaced by rating.



8,273 Points

Nevermind. I'm an idiot. I was getting the sum of Review when I should have been getting the sum of Rating


I do same type of mistakes all the time. Glad you got it resolved.