fix: reset() only drops history table, leaving stale messages (#5541)

mem0/memory/main.py

@@ -1934,10 +1934,8 @@ class Memory(MemoryBase):
         """
         logger.warning("Resetting all memories")
 
-        if hasattr(self.db, "connection") and self.db.connection:
+        self.db.reset()
-            self.db.connection.execute("DROP TABLE IF EXISTS history")
+        self.db.close()
-            self.db.connection.close()
-
         self.db = SQLiteManager(self.config.history_db_path)
 
         if hasattr(self.vector_store, "reset"):
@@ -3509,10 +3507,8 @@ class AsyncMemory(MemoryBase):
         if hasattr(self.vector_store, "client") and hasattr(self.vector_store.client, "close"):
             await asyncio.to_thread(self.vector_store.client.close)
 
-        if hasattr(self.db, "connection") and self.db.connection:
+        await asyncio.to_thread(self.db.reset)
-            await asyncio.to_thread(lambda: self.db.connection.execute("DROP TABLE IF EXISTS history"))
+        await asyncio.to_thread(self.db.close)
-            await asyncio.to_thread(self.db.connection.close)
-
         self.db = SQLiteManager(self.config.history_db_path)
 
         self.vector_store = VectorStoreFactory.create(

mem0/memory/storage.py

@@ -324,7 +324,9 @@ class SQLiteManager:
         ]
 
     def reset(self) -> None:
-        """Drop and recreate the history and messages tables."""
+        """Drop both tables. Caller is expected to replace this instance."""
+        if not self.connection:
+            raise RuntimeError("Cannot reset a closed SQLiteManager")
         with self._lock:
             try:
                 self.connection.execute("BEGIN")
@@ -335,8 +337,6 @@ class SQLiteManager:
                 self.connection.execute("ROLLBACK")
                 logger.error(f"Failed to reset tables: {e}")
                 raise
-        self._create_history_table()
-        self._create_messages_table()
 
     def close(self) -> None:
         if self.connection:

tests/memory/test_storage.py

@@ -280,3 +280,22 @@ class TestSQLiteManager:
         assert history[0]["actor_id"] is None
         assert history[0]["is_deleted"] is False
         mgr.close()
+
+    def test_reset_drops_tables(self, temp_db_path):
+        """reset() must drop both history and messages tables."""
+        mgr = SQLiteManager(temp_db_path)
+        mgr.add_history(memory_id="m1", old_memory=None, new_memory="new", event="ADD")
+        mgr.save_messages([{"role": "user", "content": "hello", "name": None}], "sess1")
+        mgr.reset()
+        tables = mgr.connection.execute(
+            "SELECT name FROM sqlite_master WHERE type='table' AND name IN ('history','messages')"
+        ).fetchall()
+        assert tables == [], "both tables should be dropped after reset"
+        mgr.close()
+
+        mgr2 = SQLiteManager(temp_db_path)
+        msg_count = mgr2.connection.execute("SELECT COUNT(*) FROM messages").fetchone()[0]
+        hist_count = mgr2.connection.execute("SELECT COUNT(*) FROM history").fetchone()[0]
+        assert msg_count == 0
+        assert hist_count == 0
+        mgr2.close()

tests/test_memory.py

@@ -118,6 +118,57 @@ def test_collection_name_preserved_after_reset(mock_sqlite, mock_llm_factory, mo
         assert reset_config.collection_name == test_collection_name, f"Reset used wrong collection name: {reset_config.collection_name}"
 
 
+@patch('mem0.utils.factory.EmbedderFactory.create')
+@patch('mem0.utils.factory.VectorStoreFactory.create')
+@patch('mem0.utils.factory.LlmFactory.create')
+def test_memory_reset_clears_messages_table(mock_llm_factory, mock_vector_factory, mock_embedder_factory, tmp_path):
+    """Regression: Memory.reset() must clear the messages table, not just history."""
+    mock_embedder_factory.return_value = MagicMock()
+    mock_vector_factory.return_value = MagicMock()
+    mock_llm_factory.return_value = MagicMock()
+
+    config = MemoryConfig()
+    config.history_db_path = str(tmp_path / "test.db")
+    memory = Memory(config)
+
+    memory.db.save_messages([{"role": "user", "content": "hello", "name": None}], "sess1")
+    memory.db.add_history(memory_id="m1", old_memory=None, new_memory="x", event="ADD")
+
+    memory.reset()
+
+    msg_count = memory.db.connection.execute("SELECT COUNT(*) FROM messages").fetchone()[0]
+    hist_count = memory.db.connection.execute("SELECT COUNT(*) FROM history").fetchone()[0]
+    assert msg_count == 0, "messages table must be empty after Memory.reset()"
+    assert hist_count == 0, "history table must be empty after Memory.reset()"
+
+
+@pytest.mark.asyncio
+@patch('mem0.utils.factory.EmbedderFactory.create')
+@patch('mem0.utils.factory.VectorStoreFactory.create')
+@patch('mem0.utils.factory.LlmFactory.create')
+async def test_async_memory_reset_clears_messages_table(mock_llm_factory, mock_vector_factory, mock_embedder_factory, tmp_path):
+    """Regression: AsyncMemory.reset() must clear the messages table, not just history."""
+    mock_embedder_factory.return_value = MagicMock()
+    mock_vector_factory.return_value = MagicMock()
+    mock_llm_factory.return_value = MagicMock()
+
+    from mem0 import AsyncMemory
+
+    config = MemoryConfig()
+    config.history_db_path = str(tmp_path / "test.db")
+    memory = AsyncMemory(config)
+
+    memory.db.save_messages([{"role": "user", "content": "hi", "name": None}], "s1")
+    memory.db.add_history(memory_id="m1", old_memory=None, new_memory="x", event="ADD")
+
+    await memory.reset()
+
+    msg_count = memory.db.connection.execute("SELECT COUNT(*) FROM messages").fetchone()[0]
+    hist_count = memory.db.connection.execute("SELECT COUNT(*) FROM history").fetchone()[0]
+    assert msg_count == 0, "messages must be empty after AsyncMemory.reset()"
+    assert hist_count == 0, "history must be empty after AsyncMemory.reset()"
+
+
 @patch('mem0.utils.factory.EmbedderFactory.create')
 @patch('mem0.utils.factory.VectorStoreFactory.create')
 @patch('mem0.utils.factory.LlmFactory.create')