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SQL Calculating,Aggregating and other functions task 2 keeps throwing an error

task 2 of SQL Calculating,Aggregating and other functions keeps throwing an error even though query seems to run with the correct results??

my query is as follows

select avg(score) as average from reviews group by movie_id HAVING average > 2;

4 Answers

Yeah, this is a bad query too. :)

You have a couple of mistakes. First you need the title FROM movies and then join it with the reviews.

The places of movies.id and reviews.id have to be the backward order (and you have a typo there... reviews.movie_id ).

Then on the outer join you need to specify LEFT OUTER JOIN so the title of the movie is the base.

And last, you've made the same mistake with the filtering. The sign has to be <.

The query should look like that:

select title, IFNULL(avg(score), 0) as average 
from movies 
on movies.id = reviews.movie_id
group by movie_id HAVING average < 2;

Oh, this one is tricky. I've spend a lot of time on this too. :)

The only problem is in the > sign. It has to be <.

The task says filter out any averages over 2, so you don't want any data elements over that. You want all elements having less that 2.

Good luck!

Thanks tihomirvelev

that worked now task three is driving me up the wall.

select title,IFNULL(avg(score),0) as average from reviews OUTER JOIN movies on reviews.id=movies.id group by movie_id HAVING average > 2;

it says something is wrong with my OUTER JOIN

thanks mate for all your help!