GraphRAG versus basic RAG: separate relationship questions from passage lookup
Use the GraphRAG paper and project documentation to compare graph structures and community summaries with passage-based retrieval for global and local questions.
Choose an approach
Start with a traceable basic RAG baseline for specific source facts. Consider GraphRAG when questions require themes or relationships across many documents. Graph structures and community summaries add ingestion steps and do not automatically correct entity errors. The methods can work together; evaluate evidence per question instead of treating graphs as a default upgrade.
Entity relationships change how material is organized
Microsoft’s GraphRAG research extracts entities and relationships and uses community summaries for collection-wide questions. Basic RAG often begins with relevant passages. The project supports different query methods; one community search does not represent every graph query. Incorrectly merging namesakes or product versions can distort relationships. Retain links to source text instead of treating an apparently definite graph edge as a verified fact.
Test local and global questions on the same material
Use identical permitted documents for date lookups and cross-document thematic questions. Record passages in the baseline and entities or summaries in the graph approach, then verify originals. Define required themes for global questions instead of relying on a subjective score. Add namesakes and conflicting versions to detect false merges. Keep generation requirements fixed and distinguish extraction errors from wording errors so gains are not mistakenly attributed to graphs rather than preprocessing or model changes.
Graph updates and summary rebuilding require maintenance
When sources are added or withdrawn, affected relationships and summaries may need updates. The GraphRAG project warns that indexing can be expensive, so validate a limited collection before importing everything. Preserve source versions and build settings and check whether summaries retain withdrawn facts. Basic retrieval may be easier to audit for narrow facts; accept graph maintenance when relationship analysis benefits important tasks. This article neither runs the project nor reproduces paper results.
Checked sources
These sources support the concepts and methods described here. Examples and test scope are labeled separately; check the version of the tools you use.