摘要
讨论了一种适合于对象关系数据库的新型索引结构———连接谓词索引 ,在介绍了谓词索引之后 ,给出了基于该索引结构的连接算法 ,并分析了连接算法的性能 ,提出了根据性能计算来确定关系R和S中谁作为外关系 ,从而降低算法代价的方法 ,特别地 ,本文还把连接谓词索引推广到一般形式 。
A new type of index structure called join predicate index( JPI ) is described. The JPI can be used to improve the performance of joins in object relational data base systems. After the introduction of JPI, a join algorithm based on JPI is presented and the performance analysis formula is given. It is also proposed which should be the outer relation so as to decrease the expense of the join operation. Lastly, the basic JPI is extended to the join of n relations.
出处
《国防科技大学学报》
EI
CAS
CSCD
2000年第1期1-6,共6页
Journal of National University of Defense Technology
基金
国家部委项目资助! (98J1 5 2 5 KG0 1 33)
