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Databases Creating and Modifying Database Tables Creating and Modifying Database Tables Making Changes to a Database

Adding foreign key not working

Hi,

I have been stuck in this challenge for some time now. They asked me to create a table and add a foreign key reference to the ID column in the table ROCKS.

I have the below statement, which I have tried in workspaces and works, but the challenge won't accept it.

CREATE TABLE MEMBERS (ID PRIMARY KEY, FIRST_NAME, LAST_NAME, FAVORITE_ROCK_ID, FOREIGN KEY(FAVORITE_ROCK_ID) REFERENCES ROCKS(ID));

The error I am getting is:

Bummer: Don't forget to add the foreign key constraint to the FAVORITE_ROCK_ID column.

Do you know how I can fix this?

Thanks!

Alejandro

2 Answers

Steven Parker
Steven Parker
231,110 Points

You'd only need the FOREIGN KEY statement when creating an association in an existing table.
When creating a new table, you can just name the column and what it refers to:

CREATE TABLE MEMBERS (ID PRIMARY KEY, FIRST_NAME, LAST_NAME, FAVORITE_ROCK_ID REFERENCES ROCKS(ID));

Thanks Steven, that is indeed the correct answer.

Just to note, when going into the sqlite documentation page (referred in the teacher notes), the first example on how to add a Foreign Key is:

CREATE TABLE track( trackid INTEGER, trackname TEXT, trackartist INTEGER, FOREIGN KEY(trackartist) REFERENCES artist(artistid) );

So I would image this method of adding a Foreign Key should be a valid answer.

Reading further though, they do mention the method you mentioned above.

Cheers,

Alejandro