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Development Tools Database Foundations Joining Relational Data Between Tables in SQL Joining Tables and Aliasing

Alex Martino
Alex Martino
367 Points

First Question of Inner Join...I don't understand.

Why doesn't this code below work? The quiz keeps saying it's not right but the results look ok.

SELECT movies.title, genres.name FROM movies LEFT OUTER JOIN genres ON movies.id= genres.id;

1 Answer

Tim Knight
Tim Knight
28,863 Points


You don't want to join on the movies.id field because that's not going to match the genres.id field. You instead want to use the movies.genre_id foreign key here, so it would actually be something like:

SELECT movies.title, genres.name 
FROM movies 
INNER JOIN genres 
ON movies.genre_id = genres.id;