Degrees of acyclicity for hypergraphs and relational database schemes

@article{Fagin1983DegreesOA,
  title={Degrees of acyclicity for hypergraphs and relational database schemes},
  author={Ronald Fagin},
  journal={J. ACM},
  year={1983},
  volume={30},
  pages={514-550}
}
  • Ronald Fagin
  • Published 1 July 1983
  • Mathematics, Computer Science
  • J. ACM
Database schemes (winch, intuitively, are collecuons of table skeletons) can be wewed as hypergraphs (A hypergraph Is a generalization of an ordinary undirected graph, such that an edge need not contain exactly two nodes, but can instead contain an arbitrary nonzero number of nodes.) A class of "acychc" database schemes was recently introduced. A number of basic desirable propemes of database schemes have been shown to be equivalent to acyclicity This shows the naturalness of the concept… Expand
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