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

Posted by Tomas Svojanovsky
Tomas Svojanovsky
26,680 Points

imported sql into XAMPP and did query -> found rows, but here get error message about OUTER JOIN

Hi, here you can see my query.

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

I did not find anything about OUTER JOIN. It seems to be old.

1 Answer

Ted Sumner
PLUS
Ted Sumner
Courses Plus Student 17,967 Points
Ted Sumner
Ted Sumner
Courses Plus Student 17,967 Points

INNER JOIN and OUTER JOIN are still supported as shown in the MySQL documentation. But, the MySQL documentation also says that you can optimize your code by using LEFT JOIN and RIGHT JOIN instead.

So, I would not say that OUTER JOIN is outdated, but I think you made a good catch on the issue. Personally, I quickly grasp the concept of INNER and OUTER JOIN, but will have to really look at how to use LEFT and RIGHT with WHERE clauses to get the same result.