Thanks Matthew & Ryan, The main inspiration behind me trying to generate Ids in sequential manner is to reduce the size of the userId, since I am using it for heavy denormalization. UUIDs are 16 bytes long, but I can also have a unique Id in just 4 bytes, and since this is just a one time process when the user signs-up, it makes sense to try cutting down the space requirements, if it is feasible "without any downsides"(!?).
I am also using userIds to attach to Id of the other data of the user on my application. If I could reduce the userId size that I can also reduce the size of other Ids, I could drastically cut down the space requirements. [Sorry for this question is not directly related to cassandra but I think Cassandra factors here because of its tuneable consistency] Regards Asil On Fri, Feb 4, 2011 at 1:09 AM, Ryan King <r...@twitter.com> wrote: > You could also consider snowflake: > > http://github.com/twitter/snowflake > > which gives you ids that roughly sort by time (but aren't sequential). > > -ryan > > On Thu, Feb 3, 2011 at 11:13 AM, Matthew E. Kennedy > <matt.kenn...@spadac.com> wrote: >> Unless you need your user identifiers to be sequential for some reason, I >> would save yourself the headache of this kind of complexity and just use >> UUIDs if you have to generate an identifier. >> >> On Feb 3, 2011, at 2:03 PM, Aklin_81 wrote: >> >>> Hi all, >>> To generate new keys/ UserIds for new users on my application, I am >>> thinking of using a simple synchronized counter that can keep track of >>> the no. of users registered on my application and when a new user >>> signs up, he can be allotted the next available id. >>> >>> Since Cassandra is eventually consistent, Is this advisable to >>> implement with Cassandra, but then I could also use stronger >>> consistency level like quorum or all for this purpose. >>> >>> >>> Please let me know your thoughts and suggesttions.. >>> >>> Regards >>> Asil >> >> > > > > -- > @rk >
