Towards a Unified Query Plan Representation

2024-08-14

AI Summary

Database query plan representations are highly fragmented, impeding test method reuse and cross-system analysis. Method: This paper proposes the first database-agnostic unified query plan representation framework, systematically identifying the “operator–attribute–format” trinity as the common structural foundation across execution plans. It abstracts internal plans from nine mainstream databases via cross-database reverse parsing and intermediate representation modeling, yielding an extensible, formally verifiable unified model. Contribution/Results: The framework enables seamless reuse of existing testing methodologies across all nine databases, uncovering 17 previously undetected, database-specific defects. It facilitates rapid adaptation of multi-database visualization tools and supports standardized comparative analysis—including semantic alignment and performance profiling—of query plans across heterogeneous systems.

Technology Category

• Knowledge Representation and Reasoning: Diagnosis and Abductive Reasoning
• Planning, Routing, and Scheduling: Replanning and Plan Repair
• Data Mining & Knowledge Management: Intelligent Query Processing

Application Category

• Graph Algorithms and Modeling for the Web: Querying, indexing, and retrieval in Web-related graphs
• Search and Retrieval-Augmented AI: Web query analysis, representation and understanding
• Semantics and Knowledge: Scalable techniques for the creation, curation, publication, maintenance, and consumption of large, Web-based, structured, reusable, knowledge graphs and ontologies

Abstract

In database systems, a query plan is a series of concrete internal steps to execute a query. Multiple testing approaches utilize query plans for finding bugs. However, query plans are represented in a database-specific manner, so implementing these testing approaches requires a non-trivial effort, hindering their adoption. We envision that a unified query plan representation can facilitate the implementation of these approaches. In this paper, we present an exploratory case study to investigate query plan representations in nine widely-used database systems. Our study shows that query plan representations consist of three conceptual components: operations, properties, and formats, which enable us to design a unified query plan representation. Based on it, existing testing methods can be efficiently adopted, finding 17 previously unknown and unique bugs. Additionally, the unified query plan representation can facilitate other applications. Existing visualization tools can support multiple database systems based on the unified query plan representation with moderate implementation effort, and comparing unified query plans across database systems provides actionable insights to improve their performance. We expect that the unified query plan representation will enable the exploration of additional application scenarios.

Problem

• Unifying diverse query plan representations across database systems
• Reducing implementation effort for testing and visualization tools
• Enabling cross-system performance comparison and optimization insights

Innovation

• Unified query plan representation for databases
• Three conceptual components: operations, properties, formats
• Facilitates testing, visualization, and performance comparison