1. graph management algorithms
   1. manage and index
      1. indexing and query processing tec
         1. how to model the data and the query
         2. how to store the data
         3. how to index the data for efficient query processing
      2. reachability queries
         1. two obvious methods(naive)
            1. breath- or depth-first search on graph O(n+m)time
            2. compute and store the edge transitive closure of the graph
            3. O(1) time
            4. O(n*n) storage
         2. compromise between above two
            1. spanning tree
            2. set covering
            3. compress the reachability information in the transitive closure and answer queries using the compressed data
      3. 概要
         1. query for tree structured data
            1. mapping tree structured data into relational schema
            2. build native XML database
         2. query for graph structured data
            1. extend a commercial RDBMS engine to support graph structured data
            2. design a special purpose graph database(Oracle Spatial network data model)
2. graph mining algorithms
   1. clustering
   2. classification
   3. frequent pattern mining
3. application