diff --git a/src/sources/sources.lisp b/src/sources/sources.lisp
index b923aff..ee6f73c 100644
--- a/src/sources/sources.lisp
+++ b/src/sources/sources.lisp
@@ -263,8 +263,8 @@
 					     ,(field-name-as-symbol name))))))
 		 `(lambda (row)
 		    (declare (optimize speed) (type list row))
-		    (destructuring-bind (&optional ,@args) row
-		      (declare (ignorable ,@args))
+		    (destructuring-bind (&optional ,@args &rest extra) row
+		      (declare (ignorable ,@args) (ignore extra))
 		      (vector ,@newrow))))))))
       ;; allow for some debugging
       (if compile (compile nil projection) projection))))
diff --git a/test/errors.load b/test/errors.load
index 3fb487b..572c5bf 100644
--- a/test/errors.load
+++ b/test/errors.load
@@ -45,5 +45,6 @@ LOAD CSV
 5|another month 13, stress retry path|2006-13-10|
 6|some null date to play with||
 7|and a ragged line|
-8|and another line|2014-01-22|
+8|and a line with extra columns|2014-01-23|hello|there|
+9|and another line|2014-01-22|