on columns for merge insert on remote tables (#4102)
Merge insert has always taken a list of columns to match on, and local tables have always joined on all of them. Remote tables did not: any list longer than one was rejected with `MergeInsertBuilder only supports a single 'on' column`, so a composite-key upsert was impossible against LanceDB Cloud and Enterprise from Rust, Python or TypeScript. The remote request now carries `on` as a list and sends it as one repeated query parameter per column — `?on=shard_key&on=id`. That is how the lance-namespace spec encodes an array-valued `on`, so the server receives a composite key in the shape it expects. A single column still serializes to `?on=id`, exactly what clients sent before, so existing callers are unaffected. A column repeated within `on` is now rejected client-side rather than sent for the server to reject with a 400. No binding changes were needed: `Table.merge_insert` in Python and `Table.mergeInsert` in TypeScript already accepted a list, it just could not reach a remote table. Both gain a test for composite keys, and the doc comments now say what passing several columns means. Part of [ENT-2084](https://linear.app/lancedb/issue/ENT-2084/mergeinsertintotablerequest-support-multiple-columns-for-the). ## Example ```python table.merge_insert(["shard_key", "id"]) \ .when_matched_update_all() \ .when_not_matched_insert_all() \ .execute(new_data) ``` A row whose `id` matches an existing row but whose `shard_key` differs is an insert, not an update. ## Not included Java. Java callers reach merge insert through `org.lance.namespace.LanceNamespace`, whose `MergeInsertIntoTableRequest.on` is a single string until lance-namespace 0.12 ([lance-namespace#363](https://github.com/lance-format/lance-namespace/pull/363), [lance#8915](https://github.com/lance-format/lance/pull/8915)). There is nothing in this repo's Java SDK to change until the `lance-core` pin can move. Sending more than one column requires a server that accepts the repeated parameter ([sophon#7571](https://github.com/lancedb/sophon/pull/7571)); an older server returns a 400 rather than silently merging on one column. Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
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.
