diff --git a/packages/common/infra/src/orm/core/__tests__/hook.spec.ts b/packages/common/infra/src/orm/core/__tests__/hook.spec.ts
index 35c1378aa5..9fd3e65c53 100644
--- a/packages/common/infra/src/orm/core/__tests__/hook.spec.ts
+++ b/packages/common/infra/src/orm/core/__tests__/hook.spec.ts
@@ -125,6 +125,6 @@ describe('ORM hook mixin', () => {
     // @ts-expect-error private
     const rawTag = client.tags.adapter.data.get(tag.id);
     expect(rawTag.color).toBe('red');
-    expect(rawTag.colors).toBe(null);
+    expect(rawTag.colors).toBe(undefined);
   });
 });
diff --git a/packages/common/infra/src/orm/core/__tests__/yjs.spec.ts b/packages/common/infra/src/orm/core/__tests__/yjs.spec.ts
index 77cd42ab26..845840e72a 100644
--- a/packages/common/infra/src/orm/core/__tests__/yjs.spec.ts
+++ b/packages/common/infra/src/orm/core/__tests__/yjs.spec.ts
@@ -368,7 +368,7 @@ describe('ORM entity CRUD', () => {
         name: 'test',
       });
 
-      expect(user.email).toBe(null);
+      expect(user.email).toBe(undefined);
     }
 
     {
diff --git a/packages/common/infra/src/orm/core/adapters/yjs/table.ts b/packages/common/infra/src/orm/core/adapters/yjs/table.ts
index e01f3f4cb3..1564fb8fe7 100644
--- a/packages/common/infra/src/orm/core/adapters/yjs/table.ts
+++ b/packages/common/infra/src/orm/core/adapters/yjs/table.ts
@@ -64,6 +64,10 @@ export class YjsTableAdapter implements TableAdapter {
 
     this.doc.transact(() => {
       for (const key in data) {
+        if (data[key] === undefined) {
+          // skip undefined fields, avoid unexpected override
+          continue;
+        }
         record.set(key, data[key]);
       }
 
diff --git a/packages/common/infra/src/orm/core/table.ts b/packages/common/infra/src/orm/core/table.ts
index bad752d2d3..02a3b93119 100644
--- a/packages/common/infra/src/orm/core/table.ts
+++ b/packages/common/infra/src/orm/core/table.ts
@@ -160,11 +160,11 @@ export class Table<T extends TableSchemaBuilder> {
 
         if (inputVal === undefined) {
           if (schema.optional) {
-            acc[key] = null;
+            acc[key] = undefined;
           }
 
           if (schema.default) {
-            acc[key] = schema.default() ?? null;
+            acc[key] = schema.default() ?? undefined;
           }
         }