mirror of
https://github.com/lancedb/lancedb.git
synced 2026-09-02 11:38:49 +00:00
Will Jones
d2ca0ce0ab
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>