Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Databases

Deepak Rohan Sekar
Deepak Rohan Sekar
9,634 Points
Posted by Deepak Rohan Sekar
Deepak Rohan Sekar
9,634 Points

Add foreign key and constraints Databases

I have to add a foreign key with constraint and reference, I think the piece of code below looks fine but it doesn't work.

1 Answer

Steven Parker
Steven Parker
230,274 Points
Steven Parker
Steven Parker
230,274 Points

I don't see any code, but just in general, the syntax to add a foreign key constraint to an existing column is:

ALTER TABLE table_name ADD CONSTRAINT constraint_name
  FOREIGN KEY (column_name) REFERENCES other_table(other_column);