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Posted by Jason Bean
Jason Bean
3,490 Points

Database Foundations Question

I'm stuck on the question below and was wondering if anyone could walk me through answering it.

Group all reviews by "movie_id" and get the average "score" and alias it as "average".

I appreciate any help. Thanks.

1 Answer

Shannon Zilka
Shannon Zilka
7,826 Points
Shannon Zilka
Shannon Zilka
7,826 Points

hard to say without seeing the data you're working with, but I imagine you have a table that has multiple scores for each movie_id, so you'd want to use 'group by' so that you're getting the average score for each movie (or movie_id) instead of just an average for the whole set of scores. The keyword you need for aliasing is 'as' - you can read more about aggregate functions like avg() here: http://www.w3schools.com/sql/sql_func_avg.asp and 'group by' here: http://www.w3schools.com/sql/sql_groupby.asp (if those links don't work, just search for w3schools and sql)