On 7/28/2005 3:45 AM, Magnus Hagander wrote:

>> >> Implementing some form of "distributed sequence" where 
>> each node uses 
>> >> separate ranges is a reasonable solution to those conflicts that 
>> >> would arise as a result of "internal interlinkages".
>> >
>> > All you do is make one db use even numbers and the other use odd by 
>> > setting start and step values of the sequence.
>> 
>> How, in that scenario, does one introduce a fifth "master node"?
>> 
>> If you have one office that is an asynchronous node, that 
>> could easily be extended to needing five offices.  Or 37 
>> remote salescritters, each with a database on their laptop...
>> 
>> It's not too difficult to solve the "distributed sequence" 
>> for the case of two nodes, as even/odd does work out quite 
>> nicely.  Generalizing is not so easy...
> 
> Make it a compound key that has one part being the node id and one part
> being a local sequence counter?

That allways works.


Jan

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