1. A method to archive data, the method comprising: electronically determining an initial data model representing functional dependencies among attributes of the data, the initial data model having fully interdependent functional dependencies among the attributes of the data; processing the initial data model in a processor-based machine to electronically prune one or more functional dependencies from the initial data model to determine a verified data model, wherein a given functional dependency indicates that a dependent attribute set depends from a key comprising a parent attribute set and processing the initial data model comprises: determining a set of candidate keys comprising respective parent attribute sets; generating a sample of the data; pruning a particular candidate key from the set of candidate keys when the sample indicates that the particular parent attribute set corresponding to the particular candidate key does not have unique entries; and archiving a transaction included in the data to memory according to the verified data model.