Re: Myltiple surrogate keys in one table!

Mikito,

I think one primary key should do .. (but that's just a gut feeling)

I can then imagine situations where you have a machine generated primary key (an object id)
and then a human readable key - like a domain primary key. That would make two with a few
special properties like the domain key can appear again for another object - the oid will
get dumped with the death of it's object and never be used again

Aside from that one thing that might help you reasoning about your problem Any additional key (be it a unique one or a dup key) will slow down inserts and updates
as the btrees with index structures need also to be written to a physical disk - rsulting
in slower overall performance

Just my two cents

Wolfgang