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

Why does my foreign key constrant not work?

I am getting an error message to add a foreign key constraint.

My Code:

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

3 Answers

You are attempting to create two primary keys in the same table. Eliminate PRIMARY KEY from your FAVORITE_ROCK_ID column so you just have:

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

Thank you Kris.

However i am still getting an error. It is saying i need to create 4 columns. which i have?

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

Ignore.... i see my mistake.

it is suppose to be CREATE TABLE MEMBERS .......NOT ROCKS.

Your statement would create a table named ROCKS. It needs to create a table named MEMBERS.