What if I don’t want AR to automatically create an integer id for a
table’s primary key? For example, if I have a habtm connecting table
I want the primary key to cover all columns in the table? I don’t see
any info about this in the docs. Is the only way of doing this to put
in an execute rule to manually drop the previously created primary key
and create my own? It seems like this is a common enough thing that
it should be added as an option to create_table.