A method and system is provided to process data transactions in a data store including a plurality of databases. The system may comprise a computer interface module to receive a data transaction request from at least one requesting computer and a data store interface module to interface the system to the plurality of databases. The system also includes a data access layer defining an abstraction layer to identify at least one database of the plurality of databases. The data transaction request may be an object orientated request and the plurality of databases may be horizontally distributed wherein the data access layer defines an object orientated abstraction layer between the computer interface module and the plurality of databases. In one embodiment a data dependent routing module is provided that generates a query to a database that is identified based on content of the data in the data transaction request.