A FalkorDB Vector Search Gotcha: Why Won't db.idx.vector.queryNodes Work?

Short summary

When using FalkorDB's db.idx.vector.queryNodes API for semantic search, vector data must meet two conditions: be stored as native vector types (via vecf32() conversion), and have an explicit vector index created. The most common pitfall is storing embeddings as plain lists or JSON strings without conversion. Always verify with typeof() to diagnose why queries return empty results or degrade to slow scans.

• •Vector data must be converted to native vector type using vecf32(), not stored as plain lists or JSON strings
• •An explicit vector index must be created with CREATE VECTOR INDEX for queries to use ANN search
• •Use typeof() to verify property type and diagnose search failures rather than inspecting values

Generated with AI, which can make mistakes.