1. A method in a computer system for restoring data from a deduplicated copy, the method comprising: receiving a request to restore to a destination location one or more data objects originally located within a hierarchy, wherein the copy of data contains information describing the hierarchy, but only contains a reduced instance of each data object of the hierarchy for storage on sequential media, and wherein the request specifies an 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 the data object itself or a reference to a data object and the data object is stored elsewhere; wherein the request contains a digest value for identifying each data object, wherein the determining comprises comparing the digest value to an index of digest values of data objects stored within the computer system; if the original location within the hierarchy specified by the request contains a reference to a data object, resolving the reference to find the 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.