Page History

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get the list of local resources

for each remote region

    get the list of remote resources

    for each resource in the local list

        if there is a remote resource that is linked to this local resource

            compare the 'modified' datetimes of local & remote resources
            if they are same, no work
            if both attribute values are same, no work
            otherwise,
                if the remote is after the local, UPDATE local attribute values to those of the remote including 'modified' timestamp
                if the local is after, no work (This will be sync'ed up in the remote region)
            remove this local from the local list
            remove this remote from the remote list

        otherwise, no work   

    for local resources that are still in the local list

        find the latest removal event of the linked resource in the remote region
        if an event is found in the remote region and the 'created' timestamp of the removal event is later than the 'created' timestamp of this local resource,
            remove the local resource with remote event 'created' timestamp
            remove this local from the local list
        otherwise, no work

    for remote resources that are still in the remote -to-do list

        find if the local resource was removed
        if it was removed and the 'removed' timestamp is later than the 'created' of the remote,
            don't create this in the local region
        otherwise,
            create this resource in the local region with remote resource attribute values including 'created', 'modified'
        remove this remote from the remote-to-do listremote list

Database Schema Changes

domain

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