Problem adding Foreign Key using Alter Table with existing MYSQL Database - can't add it! Help!

Question

I have a production database where I have renamed several column\'s that are foreign keys. Obviously mysql makes this a real pain to do in my experience.

My solution

Answer 1

Since it doesn't seem to be anything syntax-related, my best guess would be that you're running out of space for creating InnoDB tables.

EDIT: Can you paste your InnoDB configuration:

SHOW VARIABLES LIKE "inno%";