inline bool st_select_lex_unit::is_unit_op ()
{
  if (!first_select()->next_select())
  {
    if (first_select()->tvc)
      return 1;
    else
      return 0;
  }

  enum sub_select_type linkage= first_select()->next_select()->linkage;
  return linkage == UNION_TYPE || linkage == INTERSECT_TYPE ||
    linkage == EXCEPT_TYPE;
}
inline bool st_select_lex_unit::is_unit_op ()
{
  if (!first_select()->next_select())
  {
    if (first_select()->tvc)
      return 1;
    else
      return 0;
  }

  enum sub_select_type linkage= first_select()->next_select()->linkage;
  return linkage == UNION_TYPE || linkage == INTERSECT_TYPE ||
    linkage == EXCEPT_TYPE;
}