1. A computer-implemented method comprising: a client computer of a server computer in a database tier receiving from the server computer in the database tier, (a) an XML document and (b) index entry data from one or more index entries of a database index maintained by the server computer that indexes a collection of XML document including the XML document; wherein each of the one or more index entries of the database index corresponds to the one node of the XML document; wherein the index entry data comprises, for each of the one or more index entries of the database index, a hierarchy-key value, a path identifier, and a locator for the node of the XML document corresponding to the index entry of the database index; in response to the client computer receiving the XML document and the index entry data from the server computer, the client computer generating, within a volatile or non-volatile memory of the client computer, based on said index entry data from said database index, a single-scope index that indexes one or more nodes of only said XML document; wherein said single-scope index comprises one or more index entries; wherein each index entry of the one or more index entries of the single-scope index corresponds to a node of the one or more indexed nodes of the XML document; wherein generating the single-scope index comprises generating, based on the index entry data, each of the one or more index entries of the single-scope index; wherein generating each index of the one or more index entries of the single-scope index comprises generating the index entry of the single-scope index based on the hierarchy-key value, the path identifier, and the locator of the index entry data for the node corresponding to the index entry of the single-scope index; and the client computer performing a query operation involving said XML document using said single-scope index.