2011/3/7 <michael.vancanneyt@***>: > > Correct. (well, not 100%, because GUIDs are never guaranteed to be unique, > however, the possibility that 2 of them are the same is very small indeed).
Very small indeed. :) > A noticeable downside is that indexes are WAY bigger, and the queries > joining > different tables are slower, and you loose the order of creation of records. * creation order can easily be worked around by saving data with a timestamp or something - that's if creation order is actually important. In our applications a timestamp is suitable enough. * As for joining tables being slower. This is so, but the margin is so small for day-to-day usage than nobody notices any difference really. We tested our system with between 30-60 concurrent users working on our system for 8 hours a day, on a low spec workstation acting as a database server. NOTE: there are other pros to using GUID's. So too are there negatives to using DB generate/managed sequential numbers. The bottom line for us was that the pros far outweighed the cons. Your mileage my obviously vary. I would recommend each company evaluate there own needs. I just thought it might be beneficial to the original poster, to mention an alternative option for DB generated/managed primary keys. -- Regards, - Graeme - _______________________________________________ fpGUI - a cross-platform Free Pascal GUI toolkit http://fpgui.sourceforge.net -- _______________________________________________ Lazarus mailing list [email protected] http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
