On Sat, Jun 2, 2012 at 2:09 AM, Tibor Mlynarik <[email protected]> wrote: > I understand that to have implement Aggregate a la DDD, the ES > changes are the right way how to do it. Coincidentally I was reading > today about Datomic[1] and all this "do not update but add time > attribute to value" is starting to makes sense to me. > Using words from their whitepaper : The time to change that is now.
The problem with "we should change now" can be described in a 2x2 matrix; Act 0-x We don't make the change now. 1-x We make the change now. Outcome x-0 Project not successful. x-1 Project successful. 0-0 No effort spent and project dies, but some would speculate; "Because we didn't do what was right." 1-0 Effort spent and project dies, but some would speculate; "Because we wasted too much time on the next version." 0-1 We have a successful project with a big migration headache and long period of supporting both systems. 1-0 Ideal. The problem is then, if you scan through the open source landscape, you will find all of the above. And one forget that there is one variable that is "forgotten", and that is "If we had done Acted differently, would the outcome have been the same?". That no one can answer with certainty. Sometimes time is a factor, sometimes not. Sometimes the changes that were made, was not what the users wanted and so forth. The only "certainty" is that for one of the permutations (0-1), you have a hard time ahead of you. All the others, there is nothing to "worry about"... Which seems to suggest that one should try to avoid it. I am not sure, since I think it matters more whether one will die "acting"... Cheers -- Niclas Hedhman, Software Developer http://www.qi4j.org - New Energy for Java I live here; http://tinyurl.com/3xugrbk I work here; http://tinyurl.com/6a2pl4j I relax here; http://tinyurl.com/2cgsug _______________________________________________ qi4j-dev mailing list [email protected] http://lists.ops4j.org/mailman/listinfo/qi4j-dev
