diff --git a/beets/dbcore/db.py b/beets/dbcore/db.py
index d1f91389f..2745ea4c6 100644
--- a/beets/dbcore/db.py
+++ b/beets/dbcore/db.py
@@ -734,14 +734,11 @@ class Database(object):
                 return conn
 
     def _close(self):
-        """Close the current thread's connection to the underlying
-        SQLite database.
+        """Close the all connections to the underlying SQLite database.
         """
         thread_id = threading.current_thread().ident
         with self._shared_map_lock:
-            if thread_id in self._connections:
-                self._connections[thread_id].close()
-                del self._connections[thread_id]
+            self._connections.clear()
 
     @contextlib.contextmanager
     def _tx_stack(self):