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Random access with a distributed Bitmap Join Index for Star Joins.

Jaqueline J Brito1, Thiago Mosqueiro2, Ricardo R Ciferri3

  • 1University of São Paulo, São Carlos, Brazil.

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Summary
This summary is machine-generated.

We developed a distributed Bitmap Join Index (dBJI) to speed up database queries. This new index significantly improves performance for low-selectivity queries in large datasets.

Keywords:
Computer scienceDistributed Bitmap IndexHadoop ecosystemLow-selectivity queriesRandom accessStar Join

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Area of Science:

  • Database Systems
  • Distributed Computing
  • Data Management

Background:

  • Relational database performance heavily relies on indices, particularly for low-selectivity queries.
  • Star joins are common, performance-intensive operations that benefit significantly from indexing at scale.
  • Existing index-based solutions for star joins are nascent, creating a performance bottleneck.

Purpose of the Study:

  • To introduce a novel distributed Bitmap Join Index (dBJI).
  • To present a framework-agnostic strategy for efficient join predicate resolution.
  • To address the performance challenges of low-selectivity queries in large-scale star join operations.

Main Methods:

  • Development of a distributed Bitmap Join Index (dBJI).
  • Implementation of a linear-time join predicate solving strategy.
  • Empirical analysis using Hadoop technologies (HBase, Spark) and the Star Schema Benchmark (SSB).

Main Results:

  • dBJI demonstrated significant performance improvements over full scan methods.
  • Performance gains ranged from 59% to 88% for low-selectivity queries.
  • The proposed solution effectively handles join predicates in linear time.

Conclusions:

  • Distributed indices, like dBJI, can substantially boost low-selectivity query performance.
  • The dBJI approach offers a scalable and efficient solution for large databases.
  • Further development in distributed indexing is crucial for optimizing complex query operations.