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Optimized Data Indexing Algorithms for OLAP Systems

Lucian BORNAZ
2010 Database Systems Journal  
Thus, OLAP uses indexing algorithms for relational data and n-dimensional summarized data stored in cubes.  ...  This paper presents a new n-dimensional cube indexing algorithm, derived from the well known B-Tree index, which indexes data stored in data warehouses taking in consideration their multi-dimensional nature  ...  Similarly to OLTP systems, OLAP systems use indexing algorithms to optimize access to data stored in data warehouses, i.e. cubes.  ... 
doaj:b0d62204c7d54b5781bbc23032f6f411 fatcat:i5y52re6ybapnhfxne7oqcosxa

Querying data warehouses efficiently using the Bitmap Join Index OLAP Tool

Anderson Chaves Carniel, Thiago Luís Lopes Siqueira
2012 CLEI Electronic Journal  
In this paper, we introduce the BJIn OLAP Tool to efficiently perform OLAP queries over data warehouses, such as roll-up, drill-down, slice-and-dice and pivoting, by employing the bitmap join index.  ...  The bitmap join index has been recognized as an efficient mechanism to speed up queries over data warehouses.  ...  The Bitmap Join Index OLAP Tool The architecture of the Bitmap Join Index OLAP Tool (BJIn OLAP Tool) is shown in Fig. 7 .  ... 
doi:10.19153/cleiej.15.2.7 fatcat:ibrfurd6bzexjkxjrwzk7simf4

Performance comparison of property map and bitmap indexing

Ashima Gupta, Karen C. Davis, Jennifer Grommon-Litton
2002 Proceedings of the 5th ACM international workshop on Data Warehousing and OLAP - DOLAP '02  
A data warehouse is a collection of data from different sources that supports analytical querying.  ...  We identify parameters that affect performance of these indexes and determine situations in which either technique gives significant improvement over the other.  ...  INDEXING DATA WAREHOUSES Bitmap Indexes (BIs) are suitable for data warehousing environments as they consume only a fraction of the size of the indexed data and provide dramatic performance gains.  ... 
doi:10.1145/583890.583900 dblp:conf/dolap/GuptaDG02 fatcat:d7lsdqdo2baqhi5hzvzm6gv3di

Virtual denormalization via array index reference for main memory OLAP

Yansong Zhang, Xuan Zhou, Ying Zhang, Yu Zhang, Mingchuan Su, Shan Wang
2016 2016 IEEE 32nd International Conference on Data Engineering (ICDE)  
In this paper, we present A-Store, a main memory OLAP engine customized for star/snowflake schemas.  ...  Denormalization is a common tactic for enhancing performance of data warehouses, though its side-effect is quite obvious.  ...  Join index [26] is a common approach used to alleviate the cost of joins. In particular, bitmap join index is widely adopted in data warehouse products.  ... 
doi:10.1109/icde.2016.7498387 dblp:conf/icde/ZhangZZZSW16 fatcat:qrlqltkffjcjhfdur6ediuziuu

Histogram-aware sorting for enhanced word-aligned compression in bitmap indexes

Owen Kaser, Daniel Lemire, Kamel Aouiche
2008 Proceeding of the ACM 11th international workshop on Data warehousing and OLAP - DOLAP '08  
value to a k-tuple of bitmaps; At query time, you need to load k bitmaps in a look-up for one value; You trade query-time performance for fewer bitmaps; Often, fewer bitmaps translates into a smaller index  ...  ., 2005 ] process a materialized bitmap index. Slow, if uncompressed index  ...  ., 2005 ] process a materialized bitmap index. Slow, if uncompressed index does not fit in RAM.  ... 
doi:10.1145/1458432.1458434 dblp:conf/dolap/KaserLA08 fatcat:igjntfgx5rez5eh42dvfzeltnu

Virtual Denormalization via Array Index Reference for Main Memory OLAP

Yansong Zhang, Xuan Zhou, Ying Zhang, Yu Zhang, Mingchuan Su, Shan Wang
2016 IEEE Transactions on Knowledge and Data Engineering  
In this paper, we present A-Store, a main memory OLAP engine customized for star/snowflake schemas.  ...  Denormalization is a common tactic for enhancing performance of data warehouses, though its side-effect is quite obvious.  ...  Join index [26] is a common approach used to alleviate the cost of joins. In particular, bitmap join index is widely adopted in data warehouse products.  ... 
doi:10.1109/tkde.2015.2499199 fatcat:icwiwruudfdijlmt3argp73r2u

The hierarchical agglomerative clustering with Gower index: A methodology for automatic design of OLAP cube in ecological data processing context

Lucile Sautot, Bruno Faivre, Ludovic Journaux, Paul Molin
2015 Ecological Informatics  
Warehouse Our System OLAP Server OLAP Interface Dimensional data Identification of variable types Hierarchical agglomerative clustering Cube New Hierarchical dimension Cube 1  ...  Species Name Thermic index ...  ... 
doi:10.1016/j.ecoinf.2014.07.011 fatcat:3ynx76vps5edbbkvdetkornqte

Index selection for OLAP

H. Gupta, V. Harinarayan, A. Rajaraman, J.D. Ullman
Proceedings 13th International Conference on Data Engineering  
On-line analytical processing OLAP is a recent and important application of database systems. Typically, OLAP data is presented as a multidimensional data cube."  ...  OLAP queries are c omplex and can take many hours or even days to run, if executed directly on the raw data.  ...  The other approach in which the data cube is stored as a multidimensional array is known as MD-OLAP. MD-OLAP is very space consuming for sparse data cubes and hence is rarely used.  ... 
doi:10.1109/icde.1997.581755 dblp:conf/icde/GuptaHRU97 fatcat:a7n42rmgkjhltcagme3zn6n27u

Query Processing on OLAP System with Cloud Computing Environment

Nam Hun Park, Kil Hong Joo
2014 International Journal of Multimedia and Ubiquitous Engineering  
OLAP query execution costs many minutes by its enormous data and OLAP query properties. On the other hand, MOLAP has fast responses.  ...  paper, to provide not only flexibility and expandability of ROLAP but also the speediness of MOLAP, the cloud server architecture is proposed which shares clients' cube cache by P2P and manages central index  ...  Cloud OLAP Architecture This paper proposes three index layers with Cloud P2P OLAP.  ... 
doi:10.14257/ijmue.2014.9.5.16 fatcat:crfsflrewfdqtdqa352sutk6dy

Fusion OLAP: Fusing the Pros of MOLAP and ROLAP Together for In-memory OLAP

Yansong Zhang, Yu Zhang, Shan Wang, Jiaheng Lu
2018 IEEE Transactions on Knowledge and Data Engineering  
The Fusion OLAP model can be integrated into the state-of-the-art in-memory databases with additional surrogate key indexes and vector indexes.  ...  OLAP models can be categorized with two types: MOLAP (multidimensional OLAP) and ROLAP (relational OLAP).  ...  cube index for fact data.  ... 
doi:10.1109/tkde.2018.2867522 fatcat:vfrtcmiqsvfodeahtx6oake2uu

Spatial hierarchy and OLAP-favored search in spatial data warehouse

Fangyan Rao, Long Zhang, Xiu Lan Yu, Ying Li, Ying Chen
2003 Proceedings of the 6th ACM international workshop on Data warehousing and OLAP - DOLAP '03  
issue of data warehouse and OLAP.  ...  In this paper we extend the traditional set-grouping hierarchy into multi-dimensional data space and propose to use spatial index tree as the hierarchy on spatial dimension.  ...  OLAP-favored Search On GiST Generalized Index Search Tree(GiST) [14] provides a flexible index mechanism that both data and access method can be extended.  ... 
doi:10.1145/956069.956070 fatcat:qv5rcvewvnhnnjwrdwptgvr5a4

Spatial hierarchy and OLAP-favored search in spatial data warehouse

Fangyan Rao, Long Zhang, Xiu Lan Yu, Ying Li, Ying Chen
2003 Proceedings of the 6th ACM international workshop on Data warehousing and OLAP - DOLAP '03  
issue of data warehouse and OLAP.  ...  In this paper we extend the traditional set-grouping hierarchy into multi-dimensional data space and propose to use spatial index tree as the hierarchy on spatial dimension.  ...  OLAP-favored Search On GiST Generalized Index Search Tree(GiST) [14] provides a flexible index mechanism that both data and access method can be extended.  ... 
doi:10.1145/956060.956070 dblp:conf/dolap/RaoZYLC03 fatcat:p7t3mlp2ybcdvb6tcme7r4lm5a

Dynamic Multi-level Indexes for Cloud P2P OLAP

Nam Hun Park, Kil Hong Joo, Jin Tak Choi
2016 International Journal of Software Engineering and Its Applications  
OLAP query execution costs many minutes by its enormous data and OLAP query properties. On the other hand, MOLAP has fast responses.  ...  The Cloud P2P OLAP is grafted onto hierarchical hybrid P2P for fast query results and multi-dimensional range query, so that the index loads are distributed and the performance is improved..  ...  OLAP query execution costs many minutes by its enormous data and OLAP query properties.  ... 
doi:10.14257/ijseia.2016.10.2.03 fatcat:m5w7juk2sjhbvhcxzyjbmwtmbm

Development of Cloud P2P OLAP system based on balanced quadtree

Kil Hong Joo
2014 Contemporary Engineerng Sciences  
In addition, OLAP query execution costs many minutes by its enormous data and OLAP query properties.  ...  The Cloud P2P OLAP is grafted onto hierarchical hybrid P2P for fast query results and multi-dimensional range query, so that the index loads are distributed and the performance is improved.  ...  Therefore, most of the traditional OLAP research, and most of the commercial systems, follow the static data cube approach and materialize all or a subset of the cuboids of the data cube in order to ensure  ... 
doi:10.12988/ces.2014.411216 fatcat:rafihlugq5fvzmpvuqmhposmke

Yet Another Automated OLAP Workload Analyzer: Principles, and Experiences

Alfredo Cuzzocrea, Rim Moussa, Enzo Mumolo
2018 Proceedings of the 20th International Conference on Enterprise Information Systems  
(iii) to build OLAP indexes.  ...  In this paper, we share our experience of implementation of an OLAP workload analyzer, which exhaustively enumerates all materialized views, indexes and fragmentation schemas candidates.  ...  OLAP workload Performance Tuning is usually based on (i) indexes, (ii) summary data, i.e. derived attributes and aggregate tables, and (iii) data fragmentation.  ... 
doi:10.5220/0006812202930298 dblp:conf/iceis/CuzzocreaMM18 fatcat:jfcb6xhevzec5feszkvxilcsje
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