We're going to look in particular at (at least) two vector search implementation in popular tools that a lot of people already use: * pgvector for PostgreSQL * Lucene vector implementation for Elasticsearch and OpenSearch We recently had to evaluate the two for a particular use case and the comparison is quite interesting, there are pros to each, for example: * pgvector means less infra and cost, and is always strongly consistent * Elasticsearch/Opensearch can do automatic sharding * in postgres you can shard by tenant easier by using schemas or partitioned indexes * Lucene can combine functionality with full-text search We'll go through the above and also discuss when going for a dedicated vector DB makes sense.