nulldb/nulldb — pull request #13 by woahdae (2011-11-08 04:43:47+00:00)
Title: Fix 'primary_key' on primary-key-less tables

Currently, nulldb is erroring when it encounters a habtm relationship. I think it's OK for it to return nil, since this is the definition for the mysql adapters' `primary_key`:

def primary_key(table)
pk_and_sequence = pk_and_sequence_for(table)
pk_and_sequence && pk_and_sequence.first
end

The last line can return nil if pk_and_sequence is nil, so I take this to mean AR is OK with primary_key returning nil.