Vector Database vs Page Index in AI — How Modern Retrieval Systems Really Work

Q: What is the difference between vector databases and page indexes?

Vector databases store and search high-dimensional embeddings for semantic similarity. Page indexes (traditional search indexes) use inverted indexes for keyword matching. Vector databases find "similar meaning", page indexes find "exact words".

Q: When should you use a vector database?

Use vector databases for: semantic search (finding similar concepts), AI/RAG pipelines, recommendation systems, image similarity, anomaly detection, and any use case where meaning matters more than exact keyword matching.

Q: Can you use both vector search and keyword search?

Yes, hybrid search combines both approaches. Use keyword search for exact matches (product IDs, names, codes) and vector search for semantic understanding. Reranking the combined results typically yields the best accuracy.

Q: Which vector database should you choose?

Pinecone for fully managed simplicity, Qdrant for performance + open-source, Weaviate for multi-modal, pgvector for existing PostgreSQL, ChromaDB for prototyping, and Milvus for large-scale self-hosted deployments.