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Wyatt Alt
2caf8aaf47
refresh_column fills nulls, so once a row has a value nothing revisits it: an update to one of its inputs, or a definition change, leaves the computed value stale for good. This stamps the column's field metadata with the definition it was computed under and a per-fragment signature of the input storage it was read from (input data files and overlays; not the deletion file, since a delete changes no surviving value). A refresh recomputes every live row of a fragment whose stamp disagrees with the manifest, then records what it computed from in a second commit after the fill. A compacted fragment built from signed fragments inherits their freshness through the Rewrite lineage; one built from an unsigned fragment recomputes. A column declared before the stamps existed keeps the null-fill contract on its first refresh, which enrolls it as it stood. The stamp is a metadata-only commit on the computed columns, so a materialized view's drift check treats it like the fill. The core lives in `table::freshness` so a remote refresh can share the contract.
LanceDB JavaScript SDK
A JavaScript library for LanceDB.
Installation
npm install @lancedb/lancedb
This will download the appropriate native library for your platform. We currently support:
- Linux (x86_64 and aarch64 on glibc and musl)
- MacOS (Intel and ARM/M1/M2)
- Windows (x86_64 and aarch64)
Usage
Basic Example
import * as lancedb from "@lancedb/lancedb";
const db = await lancedb.connect("data/sample-lancedb");
const table = await db.createTable("my_table", [
{ id: 1, vector: [0.1, 1.0], item: "foo", price: 10.0 },
{ id: 2, vector: [3.9, 0.5], item: "bar", price: 20.0 },
]);
const results = await table.vectorSearch([0.1, 0.3]).limit(20).toArray();
console.log(results);
The quickstart contains more complete examples.
Development
See CONTRIBUTING.md for information on how to contribute to LanceDB.