1. A method in a computer system for restoring data from a single-instanced copy, the method comprising: receiving a request to restore one or more data objects originally located within a hierarchy to a destination location, wherein the copy of data contains information describing the hierarchy, but only contains a single instance of each data object with the hierarchy flattened for storage on sequential media, and wherein the request specifies the original location within the hierarchy of the data objects to be restored; for each data object in the request: determining whether the data at the original location within the hierarchy specified by the request contains a reference to a data object or the data object itself; if the original location within the hierarchy specified by the request contains a reference to a data object, resolving the reference to find the actual data object and copying the data object to the destination location; and if the original location within the hierarchy specified by the request contains the data object itself, copying the data object to the destination location.