Benno schrieb am 06.03.2012 um 20:24 (+0100): > I can't find the article, but I would NOT use GUID. > > GUID is a string, and afaik strings are not very efficient in > combination with FB. So I would use a numeric PK.
Well, it's a 128 bit (or 16 byte) integer, usually formatted as a string, like [Guid("3D27DE89-A43C-480C-866A-958E33705B19")]. http://www.firebirdfaq.org/faq98/ Visual Studio has a handy tool called guidgen.exe to create them (for COM, or possibly other stuff). That said, I second Benno's advice not to use them. Sixteen bytes, that's like 4 billion times 4 billion times 4 billion times 4 billion. A former employer used GUIDs to denote male/female. Michael