From 6ce4f842718a1e1e127fd1607b212501a1bb650d Mon Sep 17 00:00:00 2001
From: Gatefixer <313497061+lancedb-gatefixer[bot]@users.noreply.github.com>
Date: Wed, 5 Aug 2026 17:56:39 +0000
Subject: [PATCH] fix(node): validate inferred types across records

---
 nodejs/__test__/arrow.test.ts | 12 ++++++++++++
 nodejs/lancedb/arrow.ts       |  9 +++++----
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/nodejs/__test__/arrow.test.ts b/nodejs/__test__/arrow.test.ts
index 9e20e3c04..55aae754e 100644
--- a/nodejs/__test__/arrow.test.ts
+++ b/nodejs/__test__/arrow.test.ts
@@ -449,6 +449,18 @@ describe.each([arrow15, arrow16, arrow17, arrow18])(
         );
       });
 
+      it("will allow matching inferred types across records", function () {
+        expect(() =>
+          makeArrowTable([{ value: 1 }, { value: 2 }]),
+        ).not.toThrow();
+      });
+
+      it("will reject mismatched inferred types across records", function () {
+        expect(() => makeArrowTable([{ value: 1 }, { value: "two" }])).toThrow(
+          "Failed to infer schema for data. Previously inferred type Float64 but found Utf8 at row 1. Consider providing an explicit schema.",
+        );
+      });
+
       it("will allow a schema to be provided", async function () {
         await checkTableCreation(
           async (records, _, schema) =>
diff --git a/nodejs/lancedb/arrow.ts b/nodejs/lancedb/arrow.ts
index 587d30b19..b0decd481 100644
--- a/nodejs/lancedb/arrow.ts
+++ b/nodejs/lancedb/arrow.ts
@@ -489,10 +489,11 @@ function inferSchema(
       } else if (schema === undefined) {
         const currentType = pathTree.get(path);
         const newType = inferType(value, path, opts);
-        if (currentType !== newType) {
-          new Error(`Failed to infer schema for data. Previously inferred type \
-                     ${currentType} but found ${newType} at row ${rowI}. Consider \
-                     providing an explicit schema.`);
+        if (currentType?.toString() !== newType?.toString()) {
+          throw new Error(
+            `Failed to infer schema for data. Previously inferred type ${currentType} ` +
+              `but found ${newType} at row ${rowI}. Consider providing an explicit schema.`,
+          );
         }
       }
     }