1. A method, comprising: determining a difference between data stored on a first server and by an on-demand database service utilizing a data structure stored on a computer readable medium, the data structure including a plurality of user identifiers each identifying one of a plurality of users of the on-demand database service and a plurality of data identifiers each correlated with at least one of the user identifiers, the data identifiers for identifying data accessible to the user associated with the correlated user identifier; and synchronizing the first server and the on-demand database service, based on the difference.