Contextual search with vector search: exploring your options with open source tools - Olena Kutsenko

Learn about vector search implementation using open-source tools like Postgres, OpenSearch & Redis. Discover key metrics, search approaches & best practices for similarity searches.

Key takeaways
  • Vector search helps find similarities between objects by converting data into vectors in multi-dimensional space using machine learning models

  • Popular vector search databases include:

    • Postgres with pgvector
    • OpenSearch
    • Clickhouse
    • Redis
  • Key metrics for comparing vectors:

    • L2 (Euclidean) distance
    • Cosine similarity
    • Inner product
    • L1 norm
  • Two main search approaches:

    • KNN (K-Nearest Neighbors) - precise but slower
    • ANN (Approximate Nearest Neighbors) - faster but less precise
  • Important considerations for vector search:

    • Model selection should align with use case
    • Data characteristics affect index choice
    • Recall rate indicates result quality
    • Pre/post filtering can improve performance
  • Common vector search applications:

    • Semantic search
    • Recommendation systems
    • Image similarity
    • Document retrieval
  • Best practices:

    • Use batching for data ingestion
    • Consider data update frequency when choosing index
    • Combine vector search with traditional filtering
    • Test different distance metrics for your use case
  • RAG (Retrieval Augmented Generation) can be enhanced with vector search to provide context for Large Language Models

  • Vector dimensions typically range from 300-700, depending on the model used

  • Performance optimization through:

    • Efficient indexing strategies
    • Clustering similar vectors
    • Proper distance metric selection
    • Balance between precision and speed