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Development Tools Database Foundations Joining Relational Data Between Tables in SQL Keys and Auto-Incrementing Values

Binu Alexander
Binu Alexander
4,081 Points
Posted by Binu Alexander
Binu Alexander
4,081 Points

Stuck at the alter table statement

Task

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 code

alter table t_movies add constraint foreign key(fk_genre_id) references t_genres(pk_id)

What is wrong with my statement ?

2 Answers

Piotrek Smyda
Piotrek Smyda
3,786 Points
Piotrek Smyda
Piotrek Smyda
3,786 Points

Hey,

You need to add new column for foreign key.

Your statement should be like this:

alter table t_movies add column fk_genre_id integer null, add constraint foreign key (fk_genre_id) references t_genres(pk_id)
Sobin Sebastian
Sobin Sebastian
5,348 Points
Sobin Sebastian
Sobin Sebastian
5,348 Points

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