message: set for varchar, makes crossprod with string cols work
diff: @@ -606,7 +606,15 @@ void VectorOperations::Set(Vector &result, Value value) {
  // set all values in the nullmask to 0
  result.nullmask.reset();
  Vector left(value);
  + if (left.type < TypeId::VARCHAR) {
  _generic_binary_loop<operators::PickLeft>(left, result, result);
  + } else if (left.type == TypeId::VARCHAR) {
  + for (size_t i = 0; i < result.count; i++) {
  + result.SetValue(i, value);
  + }
  + } else {
  + throw NotImplementedException("Unimplemented type for Set");
  + }
  }
  }
  