Title: Quiz 3 — Vector Database Selection: Qdrant, Milvus, Weaviate, and pgvector
Course: AIINFRA 301: Production RAG & LLMOps — Observability and Evaluation > Section: Week 03 — Vector Database Selection: Qdrant, Milvus, Weaviate, and pgvector

Q: A dedicated vector database is always faster and more scalable than pgvector, so pgvector should never be used in production.
- True
- False
A: False

Q: Which vector engine is described in the lecture as the strongest default for low-latency, filtered RAG search?
- pgvector B) Qdrant C) Weaviate D) Milvus
A: pgvector B) Qdrant C) Weaviate D) Milvus

Q: At 10 million vectors under filtered-search conditions, which approximate p99 latency is associated with Qdrant?
- \~12ms B) \~16ms C) \~18ms D) \~40ms
A: \~12ms B) \~16ms C) \~18ms D) \~40ms

Q: What SQL command enables vector search capability inside Postgres?
Feedback: Sample/expected answer: CREATE EXTENSION vector;

Q: Which engine is best known for built-in hybrid search and "vectorizer" modules that generate embeddings during ingestion?
- Qdrant B) Milvus C) Weaviate D) pgvector
A: Qdrant B) Milvus C) Weaviate D) pgvector

Q: Milvus's main architectural advantage is GPU-accelerated indexing and search, making it well-suited to billion-scale collections.
- True
- False
A: True

Q: Name one of the two real constraints on pgvector discussed in the lecture (historically lower dimension cap or CPU-bound ingestion).
Feedback: Sample/expected answer: A historically lower dimension cap (commonly cited around 2000 dimensions) or CPU-bound ingestion (no native GPU bulk loading)

Q: Recent pgvector/pgvectorscale benchmarks on tens of millions of vectors show approximately what performance profile?
- Single-digit QPS at low recall B) Hundreds of QPS at \~99% recall C) They cannot complete queries at this scale D) Performance identical to unindexed full table scans
A: Single-digit QPS at low recall B) Hundreds of QPS at \~99% recall C) They cannot complete queries at this scale D) Performance identical to unindexed full table scans