feat(nodejs): add prewarmData method on Table (#3374)

### Summary
- Closes #3362 
- Adds `prewarmData(columns?: string[])` to the Node bindings, mirroring
the Rust and Python implementations

### Testing
- [x] `npm run build` (regenerates the napi `.node` module + TS
declarations)
- [x] `npm run lint`
- [x] `npm test
- [ ] live test against remote table - just waiting for my dev stack to
get created

### Documentation
- updated docs

nodejs/__test__/table.test.ts

@@ -1870,6 +1870,25 @@ describe.each([arrow15, arrow16, arrow17, arrow18])(
       expect(results.length).toBe(3);
     });
 
+    test("prewarmData errors on local tables", async () => {
+      const db = await connect(tmpDir.name);
+      const data = [
+        { text: "alpha", vector: [0.1, 0.2, 0.3] },
+        { text: "beta", vector: [0.4, 0.5, 0.6] },
+      ];
+      const table = await db.createTable("prewarm_data_test", data);
+
+      // prewarmData is only supported on remote tables. We verify the call
+      // is wired through napi and surfaces the expected error for both
+      // arg shapes (undefined and string[]).
+      await expect(table.prewarmData()).rejects.toThrow(
+        "prewarm_data is currently only supported on remote tables",
+      );
+      await expect(table.prewarmData(["text"])).rejects.toThrow(
+        "prewarm_data is currently only supported on remote tables",
+      );
+    });
+
     test("full text index on list", async () => {
       const db = await connect(tmpDir.name);
       const data = [

nodejs/lancedb/table.ts

@@ -285,6 +285,25 @@ export abstract class Table {
    */
   abstract prewarmIndex(name: string): Promise<void>;
 
+  /**
+   * Prewarm one or more columns of data in the table.
+   *
+   * @param columns The columns to prewarm. If undefined, all columns are prewarmed.
+   *
+   * This will load the column data into the page cache so that future queries that
+   * read those columns avoid the initial cold-start latency.  This call initiates
+   * prewarming and returns once the request is accepted; the warming itself may
+   * continue in the background.  Calling it on already-prewarmed columns is a
+   * no-op on the server.
+   *
+   * Prewarming is generally useful for columns used in filters or projections.
+   * Large columns (e.g. high-dimensional vectors or binary data) may not be
+   * practical to prewarm.
+   *
+   * This feature is currently only supported on remote tables.
+   */
+  abstract prewarmData(columns?: string[]): Promise<void>;
+
   /**
    * Waits for asynchronous indexing to complete on the table.
    *
@@ -710,6 +729,10 @@ export class LocalTable extends Table {
     await this.inner.prewarmIndex(name);
   }
 
+  async prewarmData(columns?: string[]): Promise<void> {
+    await this.inner.prewarmData(columns);
+  }
+
   async waitForIndex(
     indexNames: string[],
     timeoutSeconds: number,

nodejs/src/table.rs

@@ -159,6 +159,14 @@ impl Table {
             .default_error()
     }
 
+    #[napi(catch_unwind)]
+    pub async fn prewarm_data(&self, columns: Option<Vec<String>>) -> napi::Result<()> {
+        self.inner_ref()?
+            .prewarm_data(columns)
+            .await
+            .default_error()
+    }
+
     #[napi(catch_unwind)]
     pub async fn wait_for_index(&self, index_names: Vec<String>, timeout_s: i64) -> Result<()> {
         let timeout = std::time::Duration::from_secs(timeout_s.try_into().unwrap());