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This content will become publicly available on January 1, 2026

Title: Database Theory in Action: Search-Based Program Optimization
Recent work in programming languages developed an approach to term rewritings based on equality saturation (EqSat), which, instead of applying destructively the rewrite rules, maintains all equivalent expressions in a structure called an E-graph. This paper describes two surprising connections between EqSat and databases, going both ways. On one hand equality saturation can be viewed as a query evaluation problem, with great benefits. On the other hand, most sophisticated SQL query optimizers are based on the Volcano/Cascades framework which, we explain, is a variant of EqSat.  more » « less
Award ID(s):
2312195
PAR ID:
10627114
Author(s) / Creator(s):
; ; ;
Editor(s):
Roy, Sudeepa; Kara, Ahmet
Publisher / Repository:
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Date Published:
Volume:
328
ISSN:
1868-8969
ISBN:
978-3-95977-364-5
Page Range / eLocation ID:
34:1-34:6
Subject(s) / Keyword(s):
Query optimization program optimization Cascades framework equality saturation Datalog Theory of computation → Equational logic and rewriting Theory of computation → Database query processing and optimization (theory)
Format(s):
Medium: X Size: 6 pages; 793211 bytes Other: application/pdf
Size(s):
6 pages 793211 bytes
Right(s):
Creative Commons Attribution 4.0 International license; info:eu-repo/semantics/openAccess
Sponsoring Org:
National Science Foundation
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