Thank you for your reply. I read the FM. But I never believe in just one man... Most of the time, there is someone else out there who knows differently or can shine some light on the matter with a different point of view.
Why do I want a different point of view? I was told that the guid.comb was already a very good generator as a primary key, but now we noticed it also gives a lot of fragmentation. So that's why I've come to this post and asked about opinions... Maybe I've missed something about the guid.comb or maybe there are terrible facts about the sequential guids... But I'll take the advice and read more carefully :) On Sep 15, 8:34 am, Berke Sokhan <[email protected]> wrote: > If you look at the blog poster last comment at original post: > > @ramon: you should read MSDN documentation more deeply, the > > > UuidCreateSequential creates unique guid among all machines because it uses > > unique MAC address of network cards. So guid are guarantee to be unique. > > In the remote situation when the computer does not have a network card, but > > only in that situation, the guid are guarantee to be unique only on that > > machine, in that scenario the function returns the COM return value > > RPC_S_UUID_LOCAL_ONLY , so you can simply return a Guid.NewGuid (I’ll blog > > about this) [image: :)] > > I agree with you that a clustered index on Primary guid indes is indeed a > > bad choice, but since this is the default, I wish people to be aware of > > this. Using UuidCreateSequential guarantees me uniqueness, but more human > > readability, and less index fragmentation when developer does not change > > default cluster index.. thats all [image: :)] . > > ...so it seems it should unique among machines. > > stop guessing and RTFM. > > 2011/9/14 kriebb <[email protected]> > > > > > > > > > > > Hi, > > > Okay, I think I understand this... Because this kind of generation is > > one on on a machine... so two equal generations kan happen... > > > Unless off course I can reserve a byte for each machine.. (see it as a > > fixed destination byte)... > > > What I do not know (yet) is from where that dll comes from... > > > On Sep 14, 5:36 pm, TheCPUWizard <[email protected]> wrote: > > > You *MUST* ensure that there is only ONE place generating the guids that > > > way. Any type of Farm/Garden, or even clustered Sql Servers (if you are > > one > > > who runs code in the SQL environment) will cause pain. The pain may be > > > delayed, but it WILL be severe! > > > > From: [email protected] [mailto:[email protected]] On > > Behalf > > > Of John Davidson > > > Sent: Wednesday, September 14, 2011 10:58 AM > > > To: [email protected] > > > Subject: Re: [nhusers] Why use Guid.Comb? A lot more fragementation then > > > needed... > > > > I think you will get the same key generated in some cases if you run on a > > > web farm. > > > > John Davidson > > > > On Wed, Sep 14, 2011 at 10:52 AM, kriebb <[email protected]> > > wrote: > > > > Hi, > > > > We just filled up our data with some values... And we noticed that our > > > primary key index was fragemented... > > > > So we tought that the Guid.Comb was the way to go... > > > > But i've learned that actually the sequentialGuid is a far more better > > > way... > > > > I've come to this post: > > > >http://www.codewrecks.com/blog/index.php/2011/05/16/using-guid-id-in-... > > > ate-index-fragmentation/ > > > > There you can see how to use the sequential id. > > > > Now, I'm going to try it myself, but could someone tell me, why this > > > shouldn't be a part of the Nhibernate project? > > > > Or am I missing something? > > > > Thanks for discussing, > > > > -- > > > You received this message because you are subscribed to the Google Groups > > > "nhusers" group. > > > To post to this group, send email to [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected] > > > <mailto:nhusers%[email protected]> . > > > For more options, visit this group athttp:// > > groups.google.com/group/nhusers?hl=en. > > > > -- > > > You received this message because you are subscribed to the Google Groups > > > "nhusers" group. > > > To post to this group, send email to [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected]. > > > For more options, visit this group athttp:// > > groups.google.com/group/nhusers?hl=en. > > > -- > > You received this message because you are subscribed to the Google Groups > > "nhusers" group. > > To post to this group, send email to [email protected]. > > To unsubscribe from this group, send email to > > [email protected]. > > For more options, visit this group at > >http://groups.google.com/group/nhusers?hl=en. > > -- > Berke SOKHAN. > > http://twitter.com/berkesokhanhttp://blog.berkesokhan.comhttp://www.birliktegelistir.com/editors.aspx -- You received this message because you are subscribed to the Google Groups "nhusers" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.
