A new index for data warehouses



There are several auxiliary pre-computed access structures that allow faster answers by reading less base data. Examples are materialized views, join indexes, B-tree and bitmap indexes. This paper proposes dimension-join, a new type of index especially suited for data warehouses. The dimension-join borrows ideas from several concepts. It is both a bitmap index and a multi-table join and when being used one of the tables is not read to improve performance. It is a multi-table join because it holds information belonging to two tables, which is similar to the join index proposed by Valduriez. However, instead of being composed by the tables primary keys, the dimension-join index is also a bitmap index over the fact table using values from a dimension column. The dimension-join index is very useful when selecting facts depending of dimension tables belonging to snowflakes. The dimension-join represents a direct connection between the fact table and a table in the snowflake that can avoid several joins and produce enormous performance improvements. This paper also evaluates experimentally the dimension-join indexes using the TPC-H benchmark and shows that this new index structure can dramatically improve the performance for some queries.


Data Warehousing


XVI Brazilian Symposium on Databases (SBBD2001), October 2001

Cited by

Year 2005 : 1 citations

 Kamel Aouiche, "Techniques de fouille de données pour l"optimisation automatique des performances des entrepôts de données?, PhD thesis, Université Lumière Lyon 2, December 2005

Year 2004 : 2 citations

 Hayder k. Al-Ameed, Shaikha O. Al-Ketbi, Amna A. Al Kaabi, Khadija S.Al Shebli, Naila F. Al Shamsi, Noura H. Al Nuaimi, Shaikha S. Al Muhairi, "A New Oracle Text Control Panel Tool: Design And Implementation?, The 2004 International Research Conference on Innovations in Information Technology, Dubai, 2004.

 Eduardo Cunha de Almeida, "Estudo de viabilidade de uma plataforma de baixo custo para Data Warehouse?, Tese de doutoramento, Universidade Federal do Paraná, Brasil, 2004.