Vector Index#

A vector index stores embeddings so you can retrieve the items most similar to a query vector, the retrieval half of a recommender or a RAG system. In Hopsworks, a vector index is a property of an online-enabled feature group: a feature group with an embedding column can be indexed for similarity search, alongside its online and offline stores.

The vector index is backed by OpenSearch, included as a multi-tenant service in projects. OpenSearch provides the index through its k-NN plugin, which supports the FAISS and nmslib embedding indexes. Through Hopsworks, OpenSearch also provides enterprise capabilities, including authentication and access control to indexes (an index can be private to a Hopsworks project), filtering, scalability, high availability, and disaster recovery support. To learn how OpenSearch powers vector similarity search in Hopsworks, you can see this guide.