feat: support multivector for JS SDK (#2527)

Signed-off-by: BubbleCal <bubble-cal@outlook.com>

nodejs/__test__/table.test.ts

@@ -1863,4 +1863,43 @@ describe("column name options", () => {
     expect(results[0].query_index).toBe(0);
     expect(results[1].query_index).toBe(1);
   });
+
+  test("index and search multivectors", async () => {
+    const db = await connect(tmpDir.name);
+    const data = [];
+    // generate 512 random multivectors
+    for (let i = 0; i < 256; i++) {
+      data.push({
+        multivector: Array.from({ length: 10 }, () =>
+          Array(2).fill(Math.random()),
+        ),
+      });
+    }
+    const table = await db.createTable("multivectors", data, {
+      schema: new Schema([
+        new Field(
+          "multivector",
+          new List(
+            new Field(
+              "item",
+              new FixedSizeList(2, new Field("item", new Float32())),
+            ),
+          ),
+        ),
+      ]),
+    });
+
+    const results = await table.search(data[0].multivector).limit(10).toArray();
+    expect(results.length).toBe(10);
+
+    await table.createIndex("multivector", {
+      config: Index.ivfPq({ numPartitions: 2, distanceType: "cosine" }),
+    });
+
+    const results2 = await table
+      .search(data[0].multivector)
+      .limit(10)
+      .toArray();
+    expect(results2.length).toBe(10);
+  });
 });

nodejs/lancedb/arrow.ts

@@ -107,6 +107,20 @@ export type IntoVector =
   | number[]
   | Promise<Float32Array | Float64Array | number[]>;
 
+export type MultiVector = IntoVector[];
+
+export function isMultiVector(value: unknown): value is MultiVector {
+  return Array.isArray(value) && isIntoVector(value[0]);
+}
+
+export function isIntoVector(value: unknown): value is IntoVector {
+  return (
+    value instanceof Float32Array ||
+    value instanceof Float64Array ||
+    (Array.isArray(value) && !Array.isArray(value[0]))
+  );
+}
+
 export function isArrowTable(value: object): value is TableLike {
   if (value instanceof ArrowTable) return true;
   return "schema" in value && "batches" in value;

nodejs/lancedb/index.ts

@@ -100,6 +100,7 @@ export {
   RecordBatchLike,
   DataLike,
   IntoVector,
+  MultiVector,
 } from "./arrow";
 export { IntoSql, packBits } from "./util";
 

nodejs/lancedb/table.ts

@@ -6,9 +6,11 @@ import {
   Data,
   DataType,
   IntoVector,
+  MultiVector,
   Schema,
   dataTypeToJson,
   fromDataToBuffer,
+  isMultiVector,
   tableFromIPC,
 } from "./arrow";
 
@@ -346,7 +348,7 @@ export abstract class Table {
    * if the query is a string and no embedding function is defined, it will be treated as a full text search query
    */
   abstract search(
-    query: string | IntoVector | FullTextQuery,
+    query: string | IntoVector | MultiVector | FullTextQuery,
     queryType?: string,
     ftsColumns?: string | string[],
   ): VectorQuery | Query;
@@ -357,7 +359,7 @@ export abstract class Table {
    * is the same thing as calling `nearestTo` on the builder returned
    * by `query`.  @see {@link Query#nearestTo} for more details.
    */
-  abstract vectorSearch(vector: IntoVector): VectorQuery;
+  abstract vectorSearch(vector: IntoVector | MultiVector): VectorQuery;
   /**
    * Add new columns with defined values.
    * @param {AddColumnsSql[]} newColumnTransforms pairs of column names and
@@ -668,7 +670,7 @@ export class LocalTable extends Table {
   }
 
   search(
-    query: string | IntoVector | FullTextQuery,
+    query: string | IntoVector | MultiVector | FullTextQuery,
     queryType: string = "auto",
     ftsColumns?: string | string[],
   ): VectorQuery | Query {
@@ -715,7 +717,15 @@ export class LocalTable extends Table {
     return this.query().nearestTo(queryPromise);
   }
 
-  vectorSearch(vector: IntoVector): VectorQuery {
+  vectorSearch(vector: IntoVector | MultiVector): VectorQuery {
+    if (isMultiVector(vector)) {
+      const query = this.query().nearestTo(vector[0]);
+      for (const v of vector.slice(1)) {
+        query.addQueryVector(v);
+      }
+      return query;
+    }
+
     return this.query().nearestTo(vector);
   }