🎯Core Definition
GraphRAG (Microsoft's Knowledge Graph Augmented RAG architecture) is a next-generation retrieval paradigm fusing LLM information extraction with Hierarchical Community Detection; during indexing, LLMs extract Entities, Relationships, and Claims from raw corpora to synthesize a global Knowledge Graph; the Leiden algorithm partitions the graph into multi-level hierarchical communities, with LLMs authoring pre-computed Community Summaries; during querying, it supports both entity-centric Local Search and corpus-spanning Map-Reduce Global Search.
💡Use Cases
High-level thematic questions (e.g., 'What are the top 3 structural themes across the entire dataset?'), multi-hop entity relationship reasoning, and holistic enterprise audits.
⚡Key Problems Solved
Traditional vector RAG is confined to localized passage matching, completely incapable of answering holistic global sense-making questions spanning thousands of documents; GraphRAG's pre-computed graph community summaries unlock dataset-wide synthesis.