27.08.2013 23:47, Leyne, Sean wrote: > While I agree with your questions, I don't agree that Identity would be a > consideration for cluster/cloud architecture. > > Identity/Sequences are a poor fit for such usage modes, GUIDs/UUIDs are much > more appropriate, since the chances of same GUID being generated by separate > devices is extremely remote (GUIDs that are generated randomly are > statistically highly unlikely to collide in the foreseeable future)*. > > So, if cluster/cloud is a consideration, a developer needs to re-think the > use of IDENTITY in the first place.
GUIDs have its own downsides. But returning to local sequences: it is generally not a good idea from performance POV to get identity values from ordinary generators because it makes generator page hot. "Personal" generator in index root page would easy this tension. -- WBR, SD. ------------------------------------------------------------------------------ Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 2012, more! Discover the easy way to master current and previous Microsoft technologies and advance your career. Get an incredible 1,500+ hours of step-by-step tutorial videos with LearnDevNow. Subscribe today and save! http://pubads.g.doubleclick.net/gampad/clk?id=58040911&iu=/4140/ostg.clktrk Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
