无β环数据库模式研究

The Study of β-acyclic Database Scheme

无β环数据库模式是无环模式分类中的一种，无β环是相对容易满足的，且具有子图的无环性，因此具有很好的实用价值。本文给出了无β环的各种定义和定理，最后讨论了无β环的基于超图和线图的几种多项式时间算法。

β-ayclic database scheme is one of the degrees of ayclicity database scheme, β-acyclic is easy to satisfy, and its subgraph is acyclic also, so it is useful, this article gives many definition and theorem of β-acyclic, finally discusses some line time algorithm of β-ayacilic based on hypergraph and line graph.