vector db

A deceptively short interview question that's really a trap: embeddings cannot do exact match, and the interviewer knows it. What to actually turn on (payload full-text indexes, sparse vectors, metadata filters) in the vector DBs you already run.

10 billion vectors is where raw float storage (30TB) stops being an option. The answer does the HNSW vs IVF-PQ RAM math cold and shows why PQ is the only thing that fits in memory.