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Luca Poggio
Luca Poggio
3,214 Points
Posted by Luca Poggio
Luca Poggio
3,214 Points

SQL Calculating, Aggregating and Other Functions , code challenger ... what's wrong ?

I don't understand what I'm doing wrong in the last question of the code challenger within the section above.

This is the SQL I wrote

select title, IFNULL(AVG(score),0) as average from reviews LEFT OUTER JOIN movies ON movies.id = reviews.movie_id group by reviews.movie_id HAVING average < 2

I got a generic message saying that something is wrong with the statement even if the statement itself actually works.

Thanks for your help

1 Answer

Jason Anello
PLUS
Jason Anello
Courses Plus Student 94,610 Points
Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Luca,

You should be able to pass if you reverse the order of the movies and reviews tables around the LEFT OUTER JOIN

Should be:

movies LEFT OUTER JOIN reviews

Whatever table is on the left will have all of it's rows included. The table on the right will only have rows included that match the ON criteria.

The movies table should be on the left to make sure that every movie is included in the results rather than only the movies that have reviews.