Method include_down

sql/sql_lex.cc:3278–3286

include on level down */

/* include on level down */
void st_select_lex_node::include_down(st_select_lex_node *upper)
{
  if ((next= upper->slave))
    next->prev= &next;
  prev= &upper->slave;
  upper->slave= this;
  master= upper;
  slave= 0;
}


void st_select_lex_node::attach_single(st_select_lex_node *slave_arg)