diff --git a/packages/connectors/connector-mock-email-alternative/src/index.ts b/packages/connectors/connector-mock-email-alternative/src/index.ts
index 03f97d142..07f52cd40 100644
--- a/packages/connectors/connector-mock-email-alternative/src/index.ts
+++ b/packages/connectors/connector-mock-email-alternative/src/index.ts
@@ -26,7 +26,7 @@ const sendMessage =
     const config = inputConfig ?? (await getConfig(defaultMetadata.id));
     validateConfig<MockMailConfig>(config, mockMailConfigGuard);
     const { templates } = config;
-    const template = templates.find((template) => template.usageType === type);
+    const template = templates?.find((template) => template.usageType === type);
 
     assert(
       template,
diff --git a/packages/connectors/connector-mock-email-alternative/src/types.ts b/packages/connectors/connector-mock-email-alternative/src/types.ts
index c72ac0d4c..b4401c7fa 100644
--- a/packages/connectors/connector-mock-email-alternative/src/types.ts
+++ b/packages/connectors/connector-mock-email-alternative/src/types.ts
@@ -12,11 +12,13 @@ const templateGuard = z.object({
   content: z.string(), // With variable {{code}}, support HTML
 });
 
-export const mockMailConfigGuard = z.object({
-  apiKey: z.string(),
-  fromEmail: z.string(),
-  fromName: z.string().optional(),
-  templates: z.array(templateGuard),
-});
+export const mockMailConfigGuard = z
+  .object({
+    apiKey: z.string(),
+    fromEmail: z.string(),
+    fromName: z.string().optional(),
+    templates: z.array(templateGuard),
+  })
+  .partial();
 
 export type MockMailConfig = z.infer<typeof mockMailConfigGuard>;
diff --git a/packages/core/src/database/update-where.test.ts b/packages/core/src/database/update-where.test.ts
index 0943fe456..4cfbdb379 100644
--- a/packages/core/src/database/update-where.test.ts
+++ b/packages/core/src/database/update-where.test.ts
@@ -69,12 +69,20 @@ describe('buildUpdateWhere()', () => {
     ).resolves.toStrictEqual({ id: 'foo', customClientMetadata: '{"idTokenTtl":3600}' });
   });
 
-  it('throws an error when `undefined` found in values', async () => {
+  it('should skip the keys whose value is `undefined`', async () => {
+    const user: CreateUser = {
+      id: 'foo',
+      username: '456',
+    };
     const pool = createTestPool(
-      'update "users"\nset "username"=$1\nwhere "id"=$2 and "username"=$3'
+      'update "users"\nset "username"=$1\nwhere "id"=$2 and "username"=$3\nreturning *',
+      (_, [username, id]) => ({
+        id: String(id),
+        username: String(username),
+      })
     );
 
-    const updateWhere = buildUpdateWhereWithPool(pool)(Users);
+    const updateWhere = buildUpdateWhereWithPool(pool)(Users, true);
 
     await expect(
       updateWhere({
@@ -82,7 +90,7 @@ describe('buildUpdateWhere()', () => {
         where: { id: 'foo', username: '456' },
         jsonbMode: 'merge',
       })
-    ).rejects.toMatchError(new Error(`Cannot convert id to primitive`));
+    ).resolves.toStrictEqual({ ...user, username: '123' });
   });
 
   it('throws `entity.not_exists_with_id` error with `undefined` when `returning` is true', async () => {
diff --git a/packages/core/src/database/update-where.ts b/packages/core/src/database/update-where.ts
index 6d824a1dc..8f3ddfc0a 100644
--- a/packages/core/src/database/update-where.ts
+++ b/packages/core/src/database/update-where.ts
@@ -32,7 +32,7 @@ export const buildUpdateWhereWithPool =
     const connectKeyValueWithEqualSign = (data: Partial<Schema>, jsonbMode: 'replace' | 'merge') =>
       Object.entries<SchemaValue>(data)
         .map(([key, value]) => {
-          if (!isKeyOfSchema(key)) {
+          if (!isKeyOfSchema(key) || value === undefined) {
             return;
           }
 
diff --git a/packages/core/src/routes/connector/index.patch.test.ts b/packages/core/src/routes/connector/index.patch.test.ts
index abdd39ccc..5f202bcc9 100644
--- a/packages/core/src/routes/connector/index.patch.test.ts
+++ b/packages/core/src/routes/connector/index.patch.test.ts
@@ -179,6 +179,34 @@ describe('connector data routes', () => {
       );
     });
 
+    it('successfully reset connector config', async () => {
+      getLogtoConnectors.mockResolvedValue([
+        {
+          dbEntry: mockConnector,
+          metadata: { ...mockMetadata, isStandard: true },
+          type: ConnectorType.Social,
+          ...mockLogtoConnector,
+        },
+      ]);
+      updateConnector.mockResolvedValueOnce({
+        ...mockConnector,
+        config: {},
+      });
+      const response = await connectorRequest.patch('/connectors/id').send({
+        config: {},
+      });
+      expect(response).toHaveProperty('statusCode', 200);
+      expect(updateConnector).toHaveBeenCalledWith(
+        expect.objectContaining({
+          where: { id: 'id' },
+          set: {
+            config: {},
+          },
+          jsonbMode: 'replace',
+        })
+      );
+    });
+
     it('successfully updates connector config and metadata', async () => {
       getLogtoConnectors.mockResolvedValue([
         {
@@ -235,9 +263,6 @@ describe('connector data routes', () => {
         ...mockConnector,
         metadata: {
           target: 'connector',
-          name: { en: '' },
-          logo: '',
-          logoDark: '',
         },
       });
       const response = await connectorRequest.patch('/connectors/id').send({
diff --git a/packages/core/src/routes/connector/index.ts b/packages/core/src/routes/connector/index.ts
index 5c846b130..a219e6cc3 100644
--- a/packages/core/src/routes/connector/index.ts
+++ b/packages/core/src/routes/connector/index.ts
@@ -5,8 +5,10 @@ import {
   Connectors,
   ConnectorType,
   connectorResponseGuard,
+  type JsonObject,
 } from '@logto/schemas';
 import { buildIdGenerator } from '@logto/shared';
+import { conditional } from '@silverhand/essentials';
 import cleanDeep from 'clean-deep';
 import { string, object } from 'zod';
 
@@ -308,7 +310,17 @@ export default function connectorRoutes<T extends AuthedRouter>(
       }
 
       await updateConnector({
-        set: cleanDeep({ config, metadata, syncProfile }),
+        set: {
+          /**
+           * `JsonObject` has all non-undefined values, and `cleanDeep` method with default settings
+           * drops all keys with undefined values, the return type of `Partial<JsonObject>` is still `JsonObject`.
+           * The type inference failed to infer this, manually assign type `JsonObject`.
+           */
+          // eslint-disable-next-line no-restricted-syntax
+          config: conditional(config && (cleanDeep(config) as JsonObject)),
+          metadata: conditional(metadata && cleanDeep(metadata)),
+          syncProfile,
+        },
         where: { id },
         jsonbMode: 'replace',
       });
diff --git a/packages/integration-tests/src/tests/api/connector.test.ts b/packages/integration-tests/src/tests/api/connector.test.ts
index b790183ac..e20863320 100644
--- a/packages/integration-tests/src/tests/api/connector.test.ts
+++ b/packages/integration-tests/src/tests/api/connector.test.ts
@@ -115,6 +115,10 @@ test('connector set-up flow', async () => {
     currentConnectors.find((connector) => connector.connectorId === mockAlternativeEmailConnectorId)
       ?.config
   ).toEqual(mockAlternativeEmailConnectorConfig);
+  // Can reset the connector config to empty object `{}` (when it is valid).
+  await expect(updateConnectorConfig(id, { config: {} })).resolves.not.toThrow();
+  const alternativeEmailConnector = await getConnector(id);
+  expect(alternativeEmailConnector.config).toEqual({});
 
   /*
    * Delete (i.e. disable) a connector