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Sync during an uncommited transaction - missed changes? RRS feed

  • Question

  • Does the framework guarantee no missed changes if a sync (between data stored in databases) occurs whilst updates to the source database are being made in another transaction that has not yet been committed?

     

    I think that the only way to guarantee this is if the Knowledge sent from the Destination to the Source contains (summary) details about each and every Item that the Destination knows about. Is that correct? If so this could mean that the Knowledge sent is large.

     

    In our case we need to sync up to 100,000 items. Initially the number of items will be relatively small (a few hundred to a few thousand). As the list of items grows there will be a lot of changes to sync but over time the items become more static so that much fewer changes need to be synced. After a while the Item Data sent from the Source to the Destination will be small though Knowledge about the 100,000 items still needs to be sent, right? There may be a few thousand users of our application so I am concerned about the perfomance even with relatively static data.

     

    Cheers,

    Jarrod

     

     

    • Moved by Max Wang_1983 Thursday, April 21, 2011 5:59 PM forum consolidation (From:SyncFx - Technical Discussion [ReadOnly])
    Tuesday, December 2, 2008 11:20 PM

Answers

  • Knowledge is like a watermark on each site that says what its current state is with respect to the changes. If a node has seen all changes from NodeB with tick count 10, then its knowledge contains B10. Now if the 10 items have changed since that time, only those will be enumerated. If 100,000 items change, then they will be enumerated and yes it could take time. But thereafter if these items are static and do not change, then they will not need to be re-enumerated (either data or knowledge).

     

    Tuesday, December 30, 2008 1:55 AM