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PHP

Posted by Tong Vang
Tong Vang
9,926 Points

MySQL/Database Challenge

Alter the "t_movies" table to add a foreign key called "fk_genre_id" and constrain it to reference the "t_genres" "pk_id".

ALTER TABLE t_movies ADD COLUMN fk_genre_id INTEGER NULL, ADD CONSTRAINT FOREIGN KEY (pk_id), REFERENCES t_genres(pk_id);

Why is it saying "fk_genre_id" column is missing then telling me my syntax is wrong and showing me REFERENCES?

4 Answers

matthewmcdermott
matthewmcdermott
2,442 Points
matthewmcdermott
matthewmcdermott
2,442 Points

Hello Tong!

I believe that you need to change "(pk_id)" in your second line to "(fk_genre_id"). The final statement then would be:

ALTER TABLE t_movies ADD COLUMN fk_genre_id INTEGER,
ADD CONSTRAINT FOREIGN KEY (fk_genre_id) REFERENCES t_genres(pk_id)

Cheers, naano

Marc Bienaimé
Marc Bienaimé
1,116 Points
Marc Bienaimé
Marc Bienaimé
1,116 Points

no comma before REFERENCES

Tong Vang
Tong Vang
9,926 Points
Tong Vang
Tong Vang
9,926 Points

It now says...Bummer! You haven't defined the 'fk_genre_id' correctly.

Philip Cox
Philip Cox
14,818 Points
Philip Cox
Philip Cox
14,818 Points

Hi there

I to had to go over this video a few times. I think the comma trips a few people up, and referencing the correct table genre.

ALTER TABLE t_movies ADD COLUMN fk_genre_id INTEGER NULL, ADD CONSTRAINT FOREIGN KEY (fk_genre_id) REFERENCES t_genres(pk_id);

Hope this helps you. :)