Hi Guys, I've been studying Riak and am considering a major technology base shift in a project I've been working on for more then a decade (the Project Darkstar/RedDwarf game server.) As may coming to this from a strict RDBMS background I am sure, I am trying to wrap my head around vector clocks.
I read the "Why vector clocks are reasy" blog and think i follow that. My question is this: what if I have multiple data changes to multipel data structures that all have to remain in sync (be atomic)? Which data strictures are involved in any one change is not predictable. I can allow for eventual resolution of that consistent state, and even change from one consistent state to another, but the state must always be consistant. This is easy to do in a traitional transaction btu im having trouble with the VC equivalent. As a gedanken experiment picture two players trying to buy a limited commodity of which there is only 1 available. In both cases they are attempting to decrement their money, remove the object from the store inventory, and add it to their own inventory. Only one can succeed as these 3 actions must be atomic. It is okay for both to initially think they succeeded as long as next time we go to look at these states they resolve themselves. (Assume a resolution mechanism, for argument we can say earliest timestamp wins.) This needs to be a general solution, knowledge of what the data structures are or do *cannot* be part of the solution. This means that the item cant itself have an "owner" field which is part of the disambiguating logic. Disambiguating all structures (the 2 player inventories, the store inventory and the two players money values) must be done without any semantic knowledge of what the data is for. Is this possible? Can someone lay out the solution based on the simpel case above? Thanks JK Note that I need a general solutioso any -- It's always darkest just before you are eaten by a grue. _______________________________________________ riak-users mailing list riak-users@lists.basho.com http://lists.basho.com/mailman/listinfo/riak-users_lists.basho.com
