One Postgres database runs the whole graph RAG stack, post-graph-rag included
Graph RAG normally taxes you three ways: keep a vector store, a graph DB and a document store in sync, and then trust a pipeline that never refuses output. post-graph-rag collapses everything into a single PostgreSQL instance, with extraction-time checks that reject vague predicates, pronominal names and bare quantities so the graph only asserts what the prose actually says. Against LightRAG it builds a denser, more queryable graph at lower latency, and adds a temporal layer that lets a later document supersede an earlier one.