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Dai Phong
Dai Phong
20,395 Points

Problem with sql command

I'm stuck on a sql:

Like before, select the average "score" as "average", setting to 0 if null, by grouping the "movie_id" from the "reviews" table. Also, do an outer join on the "movies" table with its "id" column and display the movie "title" before the "average". Finally, filter out any "average" score over 2.

and my command is:

SELECT movies.title, IFNULL(AVG(score), 0) AS average FROM reviews LEFT OUTER JOIN movies ON reviews.movie_id = movies.id GROUP BY reviews.movie_id HAVING average < 2

But when I hit enter command, it display something wrong but still show the query result. Help me please.

1 Answer

Hi Dai,

Try this:

SELECT title, IFNULL(AVG(score),0) AS average FROM movies LEFT OUTER JOIN reviews ON movies.id = reviews.movie_id GROUP BY movie_id HAVING average <= 2;