You're doing too much work, I expect. DBIx::Class::Row->update contains-

  my %to_update = $self->get_dirty_columns
    or return $self;
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So update is already no-op if nothing has changed (it can be forced to update individual columns anyway with make_column_dirty). If you really want to know if something/anything has changed there is also the method is_changed (and is_column_changed to boot).