A pre-relational databases datamodel. "Preceeded" by the relational model since the flexibility of this makes it hard to work with. Now re-invented in RDF :)
Graph mining refers to extracting knowledge from massive graphs. The data sets of telephone calls we see at AT&T can be viewed as a single graph, with several hundred million phone numbers as nodes, and calls between phone numbers as edges. It is a giant social network, like an internet connections graph or a rich citation network.
A. Dargahi Nobari, N. Reshadatmand, und M. Neshati. Proceedings of the 2017 ACM on Conference on Information and Knowledge Management, Seite 2035–2038. New York, NY, USA, Association for Computing Machinery, (2017)