diff --git a/db/migrate/20250930230620_update_fix_term_item_relation.rb b/db/migrate/20250930230620_update_fix_term_item_relation.rb
index e4be1d8..f7c1813 100644
--- a/db/migrate/20250930230620_update_fix_term_item_relation.rb
+++ b/db/migrate/20250930230620_update_fix_term_item_relation.rb
@@ -28,7 +28,7 @@ def down
 
   def update_item_term(old_term_id, new_term_id, condition_sql)
 
-    execute <<~SQL.squish
+    execute <<~SQL.squish.freeze
       WITH target AS (
         SELECT it.term_id, it.item_id
         FROM items i