diff --git a/app/ui/sql_editor.py b/app/ui/sql_editor.py
index 40cf5e2..8fb0691 100644
--- a/app/ui/sql_editor.py
+++ b/app/ui/sql_editor.py
@@ -527,6 +527,9 @@ class EditorTab(QWidget):
         self._stop_btn.setEnabled(False)
 
     def _explain(self):
+        if not self._driver:
+            self._results.show_error("No active connection. Connect to a database first.")
+            return
         sql = self._editor.selected_or_all().strip()
         if not sql:
             return