QuaQue: Design and SQL Implementation of Condensed Algebra for Concurrent Versioning of Knowledge Graphs

TL;DR

QuaQue introduces a novel condensed algebra and SQL translation method to efficiently query concurrent versions of knowledge graphs stored in relational databases, improving performance over native RDF stores.

Contribution

It presents a new algebra and translation technique for versioned knowledge graphs, enabling efficient querying within relational databases.

Findings

Significant performance improvements over native RDF triple stores.

Effective compact storage of versioning information using bitstrings.

Successful translation from SPARQL to SQL for versioned data queries.

Abstract

The management of versioned knowledge graphs presents significant challenges, particularly in querying data across multiple versions efficiently. This paper introduces QuaQue, a key component of the ConVer-G system, which addresses this challenge by translating SPARQL (SPARQL Protocol and RDF Query Language) queries into SQL (Structured Query Language). QuaQue leverages a novel condensed algebra to operate on a relational model where versioning information is compactly stored using bitstrings. This approach allows for efficient querying of concurrent versions of knowledge graphs within a standard relational database system. We present the key concepts of our condensed algebra, detail the translation process from SPARQL algebra to SQL, and provide a comparative benchmark against a native RDF (Resource Description Framework) triple store, demonstrating the viability and performance benefits of our approach.