{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T00:03:00Z","timestamp":1756425780498,"version":"3.44.0"},"reference-count":0,"publisher":"IOS Press","isbn-type":[{"value":"9781643686165","type":"electronic"}],"license":[{"start":{"date-parts":[[2025,8,26]],"date-time":"2025-08-26T00:00:00Z","timestamp":1756166400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,8,26]]},"abstract":"<jats:p>Purpose: Existing approaches for generating Knowledge Graphs (KGs) from file-based, non-RDF data using declarative mappings are either limited by language-specific engines or lack optimization with language-independent relational algebra backends, resulting in suboptimal performance. This research proposes an integrated framework that tightly couples logical and physical plan optimizations, enabling high-performance, language-agnostic RDF graph construction. Methodology: We formalize the KG construction process using relational algebra with a dedicated RDF term generation function within the projection operator, resulting in one of two canonicalized logical plans, one with a join and one without. We then introduce tightly coupled physical operators used to define concrete execution pipelines. We propose and evaluate two optimizations, logical-level constant-folding to reduce redundant computations and a physical-level heuristic scheduling strategy to optimize concurrent execution. We implemented the optimizations in a new backend engine called konverter and benchmarked the engine with an RML frontend against two comparable engines, Morph-KGC and FlexRML. Findings: Empirical results show that constant-folding improves performance by approximately 7.4% and heuristic scheduling by approximately 14.7% compared to a worst case scenario, with minimal additional memory overhead. Overall, konverter outperforms the current state-of-the-art in performance FlexRML, reducing execution time by 61.5% and peak memory usage by 25.1%, though it currently only supports CSV files, a limitation we aim to address in future work. Value: The proposed framework and optimizations provide a formal and practically validated approach to optimizing the execution of declarative mappings for KG construction. The konverter engine demonstrates the potential for building high-performance, language-agnostic engines for enterprise KG construction.<\/jats:p>","DOI":"10.3233\/ssw250005","type":"book-chapter","created":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T08:05:28Z","timestamp":1756368328000},"source":"Crossref","is-referenced-by-count":0,"title":["Efficient Knowledge Graph Construction Based on Optimized Plans"],"prefix":"10.3233","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1601-9331","authenticated-orcid":false,"given":"Michael","family":"Freund","sequence":"first","affiliation":[{"name":"Fraunhofer Institute for Integrated Circuits IIS, N\u00fcrnberg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5836-3029","authenticated-orcid":false,"given":"Sebastian","family":"Schmid","sequence":"additional","affiliation":[{"name":"Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, N\u00fcrnberg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0702-510X","authenticated-orcid":false,"given":"Andreas","family":"Harth","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for Integrated Circuits IIS, N\u00fcrnberg, Germany"},{"name":"Friedrich-Alexander-Universit\u00e4t Erlangen-N\u00fcrnberg, N\u00fcrnberg, Germany"}]}],"member":"7437","container-title":["Studies on the Semantic Web","Linking Meaning: Semantic Technologies Shaping the Future of AI"],"original-title":[],"link":[{"URL":"https:\/\/ebooks.iospress.nl\/pdf\/doi\/10.3233\/SSW250005","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T08:05:28Z","timestamp":1756368328000},"score":1,"resource":{"primary":{"URL":"https:\/\/ebooks.iospress.nl\/doi\/10.3233\/SSW250005"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,8,26]]},"ISBN":["9781643686165"],"references-count":0,"URL":"https:\/\/doi.org\/10.3233\/ssw250005","relation":{},"ISSN":["1868-1158","2215-0870"],"issn-type":[{"value":"1868-1158","type":"print"},{"value":"2215-0870","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,8,26]]}}}