pgvector
github.com/pgvector/pgvector
A PostgreSQL extension that adds vector similarity search to your existing database, letting you store embeddings and run nearest-neighbor queries alongside regular SQL queries.
Why it is useful
If you are already running PostgreSQL, pgvector means you do not need to introduce a separate vector database service. Keeping embeddings in the same database as your application data simplifies architecture, reduces operational overhead, and lets you filter on regular columns alongside vector similarity in a single query. Handles millions of vectors adequately for most production use cases.