@inproceedings{safdarian-etal-2026-schemagraphsql,
    title = "{S}chema{G}raph{SQL}: Efficient Schema Linking with Pathfinding Graph Algorithms for Text-to-{SQL} on Large-Scale Databases",
    author = "Safdarian, AmirHossein  and
      Mohammadi, Milad  and
      Bashirloo, Ehsan Jahanbakhsh  and
      Naderi, Mona Shahamat  and
      Faili, Heshaam",
    editor = "Demberg, Vera  and
      Inui, Kentaro  and
      Marquez, Llu{\'i}s",
    booktitle = "Findings of the {A}ssociation for {C}omputational {L}inguistics: {EACL} 2026",
    month = mar,
    year = "2026",
    address = "Rabat, Morocco",
    publisher = "Association for Computational Linguistics",
    url = "https://preview.aclanthology.org/ingest-eacl/2026.findings-eacl.134/",
    pages = "2585--2599",
    ISBN = "979-8-89176-386-9",
    abstract = "Text-to-SQL systems translate natural language questions into executable SQL queries, and recent progress with large language models (LLMs) has driven substantial improvements in this task. Schema linking remains a critical component in Text-to-SQL systems, reducing prompt size for models with narrow context windows and sharpening model focus even when the entire schema fits. We present a zero-shot, training-free schema linking approach that first constructs a schema graph based on foreign key relations, then uses a single prompt to a lightweight LLM to extract source and destination tables from the user query, followed by applying classical path-finding algorithms and post-processing to identify the optimal sequence of tables and columns that should be joined, enabling the LLM to generate more accurate SQL queries. To handle real-world databases where foreign keys may be missing or inconsistent, we further propose an LLM-guided joinability discovery step that infers table connections before graph construction, ensuring robustness across diverse schemas. Despite being simple, cost-effective, and highly scalable, our method achieves state-of-the-art results on both the BIRD and Spider 2.0 benchmarks, outperforming previous specialized, fine-tuned, and complex multi-step LLM-based approaches."
}