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Development Tools Database Foundations SQL Calculating, Aggregating and Other Functions Grouping, Joining and Cleaning Up

Posted by Stefan Hoffmann
Stefan Hoffmann
24,811 Points

It asks me to group reviews by movie_id and get the average score per movie.

Why is this not right:

SELECT movie_id, AVG(score) AS average FROM reviews GROUP BY movie_id

2 Answers

Sara Chicazul
Sara Chicazul
7,475 Points

You're almost there! The key is: you don't need to include everything in your results. You can group by a column without including it in the data you select.

Stefan Hoffmann
Stefan Hoffmann
24,811 Points

You are right. I tested the "both tables have the column id" approach. This is the accepted answer. The task text is misleading.

akshaythakur
akshaythakur
33,838 Points
akshaythakur
akshaythakur
33,838 Points

Your query correct! What is problem??

Stefan Hoffmann
Stefan Hoffmann
24,811 Points

Thank you for your reply. It is correct measured by the text of the task. But since there is that hidden thing of both tables having an id column it does not pass validation. I'm sure they will fix it.