The Postgres Developer's Guide to Vector Index Tradeoffs

This story was originally published on HackerNoon at: https://hackernoon.com/the-postgres-developers-guide-to-vector-index-tradeoffs. Learn when to use HNSW, IVFFlat, StreamingDiskANN, and BM25 in Postgres. A practical guide to scaling vector search without guesswork. Check more stories related to tech-stories at: https://hackernoon.com/c/tech-stories. You can also check exclusive content about #postgres-vector-indexing, #pgvector-hnsw-vs-ivfflat, #postgres-hybrid-search-bm25, #ann-indexing-in-postgres, #pg_textsearch-vector-retrieval, #diskann-postgres-extension, #pgvectorscale-streaming, #good-company, and more. This story was written by: @tigerdata. Learn more about this writer by checking @tigerdata's about page, and for more stories, please visit hackernoon.com. Vector search in Postgres isn't about choosing the best ANN algorithm—it's about choosing the right index for your constraints. This guide explains when to use exact search, HNSW, IVFFlat, StreamingDiskANN, and BM25-based hybrid search based on memory, recall, write volume, and filter selectivity. Learn how pgvector, pgvectorscale, and pg_textsearch fit together as workloads scale.