Synchronization of change-tracked data store with data store having limited or no change tracking

A data store in which changes are not tracked is synchronized with a data store in which changes are tracked utilizing a shadow store. The shadow store contains shadow data indicative of the most recent synchronization operation between the data stores. The shadow data comprises hash values of the data items in the limited or non-change-tracked data store. Changes to data items in the limited or non-change-tracked data store are operated on to provide respective hash values. The hash values are compared with the hash values in the shadow data. If the hash values differ, changes are appropriately applied to the data store, and the shadow data is appropriately updated. In an example embodiment, hash values are obtained from one-way hash functions, such MD5, SHA-1, SHA-256, or the like.