1. A method for enumerating a graph, the method comprising: creating, by a processor, a graph for a set of data records, each data record comprising an index and one or more data elements, each data record being a vertex in the graph; creating a key for each unique value of each data element in all the vertices in the graph, each key representing an implicit edge in the graph; creating a plurality of lists of vertices, vertices in each list share a same key; for each list of vertices, determining a vertex with a least valued index in the list; and pointing the list of vertices to the vertex with the least valued index.