SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 3)
    Literal NULL (alias c_2_0)
    Identifier ref_2.c0 (alias c_2_1)
    Identifier ref_2.vkey (alias c_2_2)
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier t0 (alias ref_2)
   ExpressionList (children 2)
    OrderByElement (children 1)
     Identifier c_2_0
    OrderByElement (children 1)
     Identifier c_2_1
