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General Discussion

Posted by mahmoud saeed
mahmoud saeed
14,071 Points

Joining Table and Aliasing Code Challenge 2 of 2

Hey everyone,

I am having a hard time getting this right. Here is the question.

Like before bring back the movie 'title' and genre 'name' but use the correct OUTER JOIN to bring back all movies regardless if the 'genre_id' is set or not.

This is my query.

SELECT movies.title AS movies_title, genres.name AS genre_name FROM movies LEFT OUTER JOIN genres ON movies.id= genres.id WHERE name IS NOT NULL;

This is the error I get.

Bummer! You're not retrieving the movie 'title' first and the genre 'name' second with all information from the 'movies' table. Use an OUTER JOIN. Use LEFT if the movies table is on the left or RIGHT if it's on the right of the statement.

PLEASE HELP!!!

4 Answers

Luis Barahona
PLUS
Luis Barahona
Courses Plus Student 2,432 Points
Luis Barahona
Luis Barahona
Courses Plus Student 2,432 Points

Because you are doing an outer join, you will have all records from the movie table show up even if there is no genre id for them. Perhaps, the redundancy of the IS NOT NULL is the issue here.

Also, I can't recall - does it explicitly ask you to create an Alias for each column?

Chris Collins
Chris Collins
2,490 Points
Chris Collins
Chris Collins
2,490 Points

try this

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

Jordan Abu-Hamdeh
Jordan Abu-Hamdeh
Courses Plus Student 4,379 Points

This is the correct code for this problem by the way. All the others are a no go.

Chris Dziewa
Chris Dziewa
17,781 Points
Chris Dziewa
Chris Dziewa
17,781 Points

I did this:

SELECT movies.title, genres.name FROM movies LEFT OUTER JOIN genres ON movies.genre_id = genres.id WHERE movies.genre_id IS NOT NULL OR movies.genre_id IS NULL;

This worked fine for passing. Maybe leave out the aliasing unless the question explicitly asks for it.

Milos Rujevic
seal-mask
.a{fill-rule:evenodd;}techdegree
Milos Rujevic
Full Stack JavaScript Techdegree Student 39,661 Points
Milos Rujevic
.a{fill-rule:evenodd;}techdegree
Milos Rujevic
Full Stack JavaScript Techdegree Student 39,661 Points

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

Tina Maddox
Tina Maddox
28,102 Points

Thank you Milos!