1. A method for determining one or more life intervals for a key in a database system, comprising: (a) receiving a key for which it is desired to determine one or more life intervals; (b) walking an index structure to identify a location where the key exists or should exist; (c) reviewing past versions of the location associated with the key; (d) determining if a structural change has occurred to the location, and if so, accessing as of a time prior to the structural change; and (e) determining the one or more life intervals for the key based upon analysis of type of operation detected against the key and whether the key existed prior to the operation.