Abstract
One of the areas of data integration covers systems that maintain coherence among a heterogeneous set of databases. Such a system repeatedly collects data from the local databases, synchronizes them, and pushes the updates back.
One of the key problems in this architecture is the conflict resolution. When data in a less relevant data source changes, it should not cause any data change in a store with higher relevancy.
To meet such requirements, we propose a DataPile structure with following main advantages: effective storage of historical versions of data, straightforward adaptation to global schema changes, separation of data conversion and replica-tion logic, simple implementation of data relevance. Key usage of such mechanisms is in projects with following traits or require-ments: integration of heterogeneous data from sources with different reliability, data coherence of databases whose schema differs, data changes are performed on local databases and minimal load on the central database.