## Problem
When applying hard filters that result in zero matches, hybrid search
crashes with `IndexError: list index out of range` during reranking.
This happens because empty result tables are passed through the full
reranker pipeline, which expects at least one result.
Traceback from the issue:
```
lancedb/query.py: in _combine_hybrid_results
results = reranker.rerank_hybrid(fts_query, vector_results, fts_results)
lancedb/rerankers/answerdotai.py: in rerank_hybrid
combined_results = self._rerank(combined_results, query)
...
IndexError: list index out of range
```
## Fix
Added an early return in `_combine_hybrid_results` when both vector and
FTS results are empty. Instead of passing empty tables through
normalization, reranking, and score restoration (which can fail in
various ways), we now build a properly-typed empty result table with the
`_relevance_score` column and return it directly.
## Test
Added `test_empty_hybrid_result_reranker` that exercises
`_combine_hybrid_results` directly with empty vector and FTS tables,
verifying:
- Returns empty table with correct schema
- Includes `_relevance_score` column
- Respects `with_row_ids` flag
Closes #2425
The Multimodal AI Lakehouse
How to Install ✦ Detailed Documentation ✦ Tutorials and Recipes ✦ Contributors
The ultimate multimodal data platform for AI/ML applications.
LanceDB is designed for fast, scalable, and production-ready vector search. It is built on top of the Lance columnar format. You can store, index, and search over petabytes of multimodal data and vectors with ease. LanceDB is a central location where developers can build, train and analyze their AI workloads.
Demo: Multimodal Search by Keyword, Vector or with SQL
Star LanceDB to get updates!
Key Features:
- Fast Vector Search: Search billions of vectors in milliseconds with state-of-the-art indexing.
- Comprehensive Search: Support for vector similarity search, full-text search and SQL.
- Multimodal Support: Store, query and filter vectors, metadata and multimodal data (text, images, videos, point clouds, and more).
- Advanced Features: Zero-copy, automatic versioning, manage versions of your data without needing extra infrastructure. GPU support in building vector index.
Products:
- Open Source & Local: 100% open source, runs locally or in your cloud. No vendor lock-in.
- Cloud and Enterprise: Production-scale vector search with no servers to manage. Complete data sovereignty and security.
Ecosystem:
- Columnar Storage: Built on the Lance columnar format for efficient storage and analytics.
- Seamless Integration: Python, Node.js, Rust, and REST APIs for easy integration. Native Python and Javascript/Typescript support.
- Rich Ecosystem: Integrations with LangChain 🦜️🔗, LlamaIndex 🦙, Apache-Arrow, Pandas, Polars, DuckDB and more on the way.
How to Install:
Follow the Quickstart doc to set up LanceDB locally.
API & SDK: We also support Python, Typescript and Rust SDKs
| Interface | Documentation |
|---|---|
| Python SDK | https://lancedb.github.io/lancedb/python/python/ |
| Typescript SDK | https://lancedb.github.io/lancedb/js/globals/ |
| Rust SDK | https://docs.rs/lancedb/latest/lancedb/index.html |
| REST API | https://docs.lancedb.com/api-reference/rest |
Join Us and Contribute
We welcome contributions from everyone! Whether you're a developer, researcher, or just someone who wants to help out.
If you have any suggestions or feature requests, please feel free to open an issue on GitHub or discuss it on our Discord server.
Check out the GitHub Issues if you would like to work on the features that are planned for the future. If you have any suggestions or feature requests, please feel free to open an issue on GitHub.
