Abstract: The present disclosure relates to a method in a distributed and non-hierarchical node comprising a set of data items for determining a synchronization state between said node and one or more distributed and non-hierarchical nodes communicatively coupled to form a cluster, wherein the set of data items are locally replicated at each node. The method comprises generating a snapshot comprising information relating to the set of data items at a snapshot time Ts, said information identifying changes to the data items where each change comprises a time stamp, where only changes to the data items with a time stamp<T0, where Ts>T0, are included in the snapshot, although changes to the data items up to the time Ts, have been received and stored in the nodes, receiving corresponding generated snapshots from all other nodes in the cluster, and determining a synchronization state based on a comparison between the generated and received snapshots.
Abstract: The present disclosure relates to a method for determining a synchronization state between a primary database 250 and one or more secondary databases communicatively coupled with the primary database to form a distributed and nonhierarchical database cluster, wherein the primary and secondary databases store attributes 320 of spatial entities 300 of a space modeled using a spatial model, and each database comprises data entities representing spatial entities 300 with defined spatial boundaries within at least a segment of the spatial model, where the attributes 320 of the spatial entities 300 are coupled to the data entities.
Abstract: The present disclosure relates to a method in a distributed and non hierarchical node comprising a set of data items for determining a synchronization state between said node and one or more distributed and non hierarchical nodes communicatively coupled to form a cluster, wherein the set of data items are locally replicated at each node. The method comprises generating a snapshot comprising information relating to the set of data items at a snapshot time Ts, said information identifying changes to the data items where each change comprises a time stamp, where only changes to the data items with a time stamp<To, where Ts>To, are included in the snapshot, although changes to the data items up to the time Ts have been received and stored in the nodes, receiving corresponding generated snapshots from all other nodes in the cluster, and determining a synchronization state based on a comparison between the generated and received snapshots.