Table without primary key

I agree that this is a great gem, but you wrote that your table didn't have a primary key. Did you or a DBA create a compound one instead of a simple one? Or, did you have a compound one all along?

Craig

Did you or a DBA create a compound one instead of a simple one?
Or, did you have a compound one all along?

No.
Table had not any PK.
Table has not any PK now.
I tried use set_primary_key :column_name but it didn't work. When i
tried to save row i had got error. I don't know why.
I tried use this gem and use set_primary_keys :column_name - it
works.