提出利用Cube中的维层次聚集树(d im ens ion h ierarchy aggregate tree,简称DHA_T ree)来对聚集Cube进行增量更新维护,在维层次聚集Cube中进行数据插入和删除等数据更新时,充分利用维层次聚集树中的维层次前缀,由下向上用更新前后的...提出利用Cube中的维层次聚集树(d im ens ion h ierarchy aggregate tree,简称DHA_T ree)来对聚集Cube进行增量更新维护,在维层次聚集Cube中进行数据插入和删除等数据更新时,充分利用维层次聚集树中的维层次前缀,由下向上用更新前后的差值对受到更新结点影响的所有祖先结点进行增量更新.在插入新维数据时,在不需要重新构建聚集Cube就可以对聚集Cube进行增量更新,从而减少了Cube的更新时间.对基于维层次聚集树的聚集Cube与传统Cube进行了算法性能分析和比较,结果表明本文所提出的聚集Cube的增量更新算法性能最佳.展开更多
The analysis of relevant standards and guidelines proved the lack of information on actions and activities concerning data warehouse testing. The absence of the complex data warehouse testing methodology seems to be c...The analysis of relevant standards and guidelines proved the lack of information on actions and activities concerning data warehouse testing. The absence of the complex data warehouse testing methodology seems to be crucial particularly in the phase of the data warehouse implementation. The aim of this article is to suggest basic data warehouse testing activities as a final part of data warehouse testing methodology. The testing activities that must be implemented in the process of the data warehouse testing can be split into four logical units regarding the multidimensional database testing, data pump testing, metadata and OLAP (Online Analytical Processing) testing. Between main testing activities can be included: revision of the multidimensional database scheme, optimizing of fact tables number, problem of data explosion, testing for correctness of aggregation and summation of data etc.展开更多
Data structure and semantics of the traditional data model cannot effectively represent the data warehouse, it is difficult to effectively support online analytical processing (referred to as OLAP). This paper is pr...Data structure and semantics of the traditional data model cannot effectively represent the data warehouse, it is difficult to effectively support online analytical processing (referred to as OLAP). This paper is propose a new multidimensional data model based on the partial ordering and mapping. The data model can fully express the complex data structure and semantics of data warehouse, and provide an OLAP operation as the core of the operation of algebra, support structure in levels of complex aggregation operation sequence, which can effectively support the application of OLAE The data model supports the concept of aggregation function constraint, and provides constraint mechanism of the hierarchy aggregation function.展开更多
文摘提出利用Cube中的维层次聚集树(d im ens ion h ierarchy aggregate tree,简称DHA_T ree)来对聚集Cube进行增量更新维护,在维层次聚集Cube中进行数据插入和删除等数据更新时,充分利用维层次聚集树中的维层次前缀,由下向上用更新前后的差值对受到更新结点影响的所有祖先结点进行增量更新.在插入新维数据时,在不需要重新构建聚集Cube就可以对聚集Cube进行增量更新,从而减少了Cube的更新时间.对基于维层次聚集树的聚集Cube与传统Cube进行了算法性能分析和比较,结果表明本文所提出的聚集Cube的增量更新算法性能最佳.
文摘The analysis of relevant standards and guidelines proved the lack of information on actions and activities concerning data warehouse testing. The absence of the complex data warehouse testing methodology seems to be crucial particularly in the phase of the data warehouse implementation. The aim of this article is to suggest basic data warehouse testing activities as a final part of data warehouse testing methodology. The testing activities that must be implemented in the process of the data warehouse testing can be split into four logical units regarding the multidimensional database testing, data pump testing, metadata and OLAP (Online Analytical Processing) testing. Between main testing activities can be included: revision of the multidimensional database scheme, optimizing of fact tables number, problem of data explosion, testing for correctness of aggregation and summation of data etc.
文摘Data structure and semantics of the traditional data model cannot effectively represent the data warehouse, it is difficult to effectively support online analytical processing (referred to as OLAP). This paper is propose a new multidimensional data model based on the partial ordering and mapping. The data model can fully express the complex data structure and semantics of data warehouse, and provide an OLAP operation as the core of the operation of algebra, support structure in levels of complex aggregation operation sequence, which can effectively support the application of OLAE The data model supports the concept of aggregation function constraint, and provides constraint mechanism of the hierarchy aggregation function.