diff --git a/api/models/chatflow_memory.py b/api/models/chatflow_memory.py
index 773c69405d..b02b809cd7 100644
--- a/api/models/chatflow_memory.py
+++ b/api/models/chatflow_memory.py
@@ -67,7 +67,10 @@ class ChatflowMessage(Base):
 
     id: Mapped[str] = mapped_column(StringUUID, primary_key=True, server_default=sa.text("uuid_generate_v4()"))
     conversation_id: Mapped[str] = mapped_column(StringUUID, nullable=False)
-    index: Mapped[int] = mapped_column(sa.Integer, nullable=False)
+    index: Mapped[int] = mapped_column(sa.Integer, nullable=False) # This index starts from 0
     version: Mapped[int] = mapped_column(sa.Integer, nullable=False)
     data: Mapped[str] = mapped_column(sa.Text, nullable=False)  # Serialized PromptMessage JSON
     created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False, server_default=func.current_timestamp())
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime, nullable=False, server_default=func.current_timestamp(), onupdate=func.current_timestamp()
+    )
diff --git a/api/services/chatflow_history_service.py b/api/services/chatflow_history_service.py
index 915d5ff2c8..521cf22218 100644
--- a/api/services/chatflow_history_service.py
+++ b/api/services/chatflow_history_service.py
@@ -68,21 +68,21 @@ class ChatflowHistoryService:
             next_index = max_index + 1
 
             # Save new message to append-only table
-            message_data = {
-                'role': prompt_message.role.value,
-                'content': prompt_message.get_text_content(),
-                'timestamp': time.time()
-            }
-
             new_message = ChatflowMessage(
                 conversation_id=chatflow_conv.id,
                 index=next_index,
                 version=1,
-                data=json.dumps(message_data)
+                data=json.dumps(prompt_message)
             )
             session.add(new_message)
             session.commit()
 
+            # 添加：每次保存消息后简单增长visible_count
+            current_metadata = ChatflowConversationMetadata.model_validate_json(chatflow_conv.conversation_metadata)
+            new_visible_count = current_metadata.visible_count + 1
+            new_metadata = ChatflowConversationMetadata(visible_count=new_visible_count)
+            chatflow_conv.conversation_metadata = new_metadata.model_dump_json()
+
     @staticmethod
     def save_app_message(
         prompt_message: PromptMessage,
@@ -209,7 +209,7 @@ class ChatflowHistoryService:
         else:
             if create_if_missing:
                 # Create a new chatflow conversation
-                default_metadata = ChatflowConversationMetadata(visible_count=20)
+                default_metadata = ChatflowConversationMetadata(visible_count=0)
                 new_chatflow_conv = ChatflowConversation(
                     tenant_id=tenant_id,
                     app_id=app_id,
diff --git a/api/services/chatflow_memory_service.py b/api/services/chatflow_memory_service.py
index 23e9f4174d..0e6e064b89 100644
--- a/api/services/chatflow_memory_service.py
+++ b/api/services/chatflow_memory_service.py
@@ -549,6 +549,15 @@ class ChatflowMemoryService:
         )
         ChatflowMemoryService.save_memory(updated_memory, variable_pool, is_draft)
 
+        # 添加以下代码：重置 visible_count 为 preserved_turns
+        ChatflowHistoryService.update_visible_count(
+            conversation_id=memory_block.conversation_id,
+            node_id=memory_block.node_id,
+            new_visible_count=memory_block.spec.preserved_turns,
+            app_id=memory_block.app_id,
+            tenant_id=memory_block.tenant_id
+        )
+
     @staticmethod
     def delete_memory(app: App, memory_id: str, created_by: MemoryCreatedBy):
         workflow = WorkflowService().get_published_workflow(app)