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Posted by Reed Mangino
Reed Mangino
1,621 Points

MySQL Keys and Autoincrementing Values challenge

Hi,

I'm being asked, "Alter the "t_movies" table to add a foreign key called "fk_genre_id" and constrain it to reference the "t_genres" "pk_id".

My answer is:

alter table t_movies add column fk_genre_id integer, add constraint foreign key (fk_genre_id) references t_genres(pk_id);

which is wrong but I don't know why.

2 Answers

Reed Mangino
Reed Mangino
1,621 Points
Reed Mangino
Reed Mangino
1,621 Points

I typed it in one last time and it was accepted as correct - no idea what was wrong.

mnwogdbvte
mnwogdbvte
16,349 Points
mnwogdbvte
mnwogdbvte
16,349 Points

I was having the same exact problem, and believe I found the correct solution:

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