关键词: 对象代理数据库, 倒排路径索引, 路径表达式, 查询优化, 灵活性

Abstract: Existing index structures for evaluating path expression in object deputy database all have an obvious disadvantage which is lack of flexibility. To solve this problem, this paper proposes an index structure: inverted path index (IPI), which can not only be used flexibly for any path expression, but also effectively reduce the cost of evaluation. IPI consists of Inverted-Object-Index and Predicate-Index, the former uses inverted index to store the deputy relationship between objects, and the latter facilitates the associative search of objects. Based on IPI index structure, IPI index method is designed and implemented to evaluate path expression. The experiments are taken on various influential factors of path expression evaluation, and the experimental results show that IPI index method can evaluate path expression efficiently, and its flexibility outperforms the other methods in most cases.

Key words: object deputy database, inverted path index, path expression, query optimization, flexibility