Oracle Corporation
IDENTIFYING AND RESOLVING DIFFERENCES BETWEEN DATASTORES

Abstract:

Techniques for efficiently maintaining consistency of data items across storage partitions are disclosed using a hierarchical multi-level hash tree. Copies of a data item may be associated with corresponding attributes that are used to generate hash values for the data item. Hash values of the attributes may then be used to label nodes in a multi-level hash tree. Differences between the replicated copies of a data item may be quickly identified by comparing hash values associated with successively lower peer nodes in corresponding hash trees. Once identified, systems may update versions of a data item that are no longer current.