复习多查询优化:一个全查询的代数方法
Yicheng Tu1, Mehrad Eslami1, Zichen Xu2
1Dept. of Computer Science, University of South Florida, Tampa, Florida, USA.
概括
通过创建一个包含所有必要数据的表达式,PsiDB将许多数据库查询一起处理. 这个系统使用了新的操作员和优化规则,显著提高了性能.
科学领域:
- 数据库系统 数据库系统
- 查询处理和优化查询处理和优化
背景情况:
- 数据共享和对并发查询的计算是数据库系统的一个关键研究领域.
- 现有的系统缺乏用于查询处理和优化的强有力的逻辑基础.
- 需要有效的方法来同时处理大量的数据库查询.
研究的目的:
- 介绍PsiDB,一种用于批处理众多数据库查询的新型系统模型.
- 在并发环境中引入用于查询处理和优化的逻辑框架.
- 为并发查询开发新的代数优化技术.
主要方法:
- 开发了PsiDB,这是一个系统模型,用于批处理生成单个查询表达式.
- 建议使用专门的关系运算符,称为Psi运算符,用于结合查询.
- 制定了代数等效规则,以转换并发查询并确定优化机会.
主要成果:
- 该PsiDB模型有效地将单个查询结合到一个全局表达式中.
- 开发了围绕Psi-operator的优化规则,包括现有的技术和揭示新的技术.
- 实验结果显示,与主流商业DBMS相比,性能提高了36倍.
结论:
- PsiDB为并发查询处理和优化提供了一个强大的逻辑基础.
- 拟议的Psi-operators和优化规则提供了显著的性能优势.
- 在大量数据库查询的批处理中,PsiDB表现出卓越的效率.
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