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Databases

Dan Boswell
Dan Boswell
2,570 Points
Posted by Dan Boswell
Dan Boswell
2,570 Points

Why does my SQL statement return 0.0 when using the SUM function?

SELECT SUM(review) AS starman_total_ratings FROM reviews WHERE movie_id = 6;

3 Answers

Dan Boswell
Dan Boswell
2,570 Points
Dan Boswell
Dan Boswell
2,570 Points

I solved my own problem.... I was selecting the wrong column (duh!). I needed to SUM the rating column not the review column.

Thomas Nilsen
Thomas Nilsen
14,957 Points
Thomas Nilsen
Thomas Nilsen
14,957 Points

Unless "review" is a numerical column, use count(review) instead

Dan Boswell
Dan Boswell
2,570 Points
Dan Boswell
Dan Boswell
2,570 Points

This won't work. I have to use the SUM function in this challenge. Here is the question for context...

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 in the reviews table. Alias it as starman_total_ratings.