A system and method for managing data updates by cascading those updates through
a virtual copy hierarchy from parent copies to child copies are provided. Virtual
copies are created and managed through the use of an instant copy mechanism. Metadata
subsets manage both the original data and the copies created by the instant copy
mechanism. With an exemplary embodiment of the system and method, changes made
to one copy of the data are cascaded to all child copies of the data. In this paradigm
not only is the metadata entry for one particular copy changed, but also the corresponding
metadata entries of any copies descended from that copy. In an exemplary method,
a tree structure is used to maintain a record of all metadata table subsets created
by use of an instant copy method. The tree structure can then be searched to find
all child copies of a particular copy.