An Algebraic Foundation for Knowledge Graph Construction (Extended Version)
Abstract
Although they exist since more than ten years already, have attracted diverse implementations, and have been used successfully in a significant number of applications, declarative mapping languages for constructing knowledge graphs from heterogeneous types of data sources still lack a solid formal foundation. This makes it impossible to introduce implementation and optimization techniques that are provably correct and, in fact, has led to discrepancies between different implementations. Moreover, it precludes studying fundamental properties of different languages (e.g., expressive power). To address this gap, this paper introduces a language-agnostic algebra for capturing mapping definitions. As further contributions, we show that the popular mapping language RML can be translated into our algebra (by which we also provide a formal definition of the semantics of RML) and we prove several algebraic rewriting rules that can be used to optimize mapping plans based on our algebra.
Cite
@article{arxiv.2503.10385,
title = {An Algebraic Foundation for Knowledge Graph Construction (Extended Version)},
author = {Sitt Min Oo and Olaf Hartig},
journal= {arXiv preprint arXiv:2503.10385},
year = {2025}
}
Comments
This is an extended version of a research paper accepted for the 22nd Extended Semantic Web Conference (ESWC 2025). The extension consists of a few additional equivalences in Section 6.1 and the complete content of Section 6.2, which are not included in the version prepared for the conference proceedings