1. A computer implemented method including a plurality of data objects stored in a plurality databases, a method implemented in instructions executed by a computer processor for processing data stored on a database, the method comprising: associating each a data object in the plurality of data objects in the plurality of databases with a data object ontology corresponding to a hierarchy data object of dimensions of the data object, wherein the hierarchy comprises having at least one source dimension; and one or more target dimensions dependent on each source dimension and wherein each dimension associated with a specific attribute data; and for each data object of the plurality of data objects: based upon values of specific attribute data of a subset of data object dimensions associated with the data object comprising a source dimension and one or more dependent target dimensions; providing the unique identifier to identify the data object; calculating and associating a unique identifier for each data object based on applying a hashing algorithm executed by the computer processor to data stored on the database to a selected set of the objects' dimensions having the highest affinity metric values, and wherein the affinity metric for each dimension is calculated as a weighted sum of temporal invariance of a dimension and a uniqueness metric, wherein: the temporal invariance of the object dimension is calculated as the minimum of the temporal invariance of any value appearing in the object dimension, the temporal invariance being calculated as the ratio of the number of times the value of the object dimension has changed over the total number of times the value of the dimension is observed in the databases over a period of time; and the uniqueness metric capturing whether data values in an object dimension are unique.