Vector Indexing & Optimization
Overview
Index types, quantization, and reindexing strategies for LanceDB vector search performance.
Quick Reference
Index Types
| Index | Best For | Quantization |
|---|---|---|
| IVF_PQ | General purpose | Product Quantization |
| IVF_HNSW_SQ | High recall | Scalar Quantization |
| IVF_HNSW_PQ | Large datasets | Product Quantization |
| IVF_FLAT | Small datasets, 100% recall | None |
| IVF_RQ | Binary vectors | RaBitQ (1 bit/dim) |
Quantization
| Type | Bits/Dim | Compression | Recall Impact |
|---|---|---|---|
| None | 32 | 1x | None |
| SQ | 8 | 4x | Minimal |
| PQ | 4-8 | 4-8x | Moderate |
| RQ (RaBitQ) | 1 | 32x | Low-moderate |
Reindexing
table.optimize() # Compaction + cleanup + index update
References
- Vector Index Types — IVF, HNSW, PQ, RQ index selection and tuning
- Indexing Concepts — Internal mechanics, disk-based indexing
- Quantization — Compression techniques, accuracy tradeoffs
- Reindexing — Incremental updates, compaction, optimization