SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 6)
    Identifier t.a
    Identifier t.a (alias t_a)
    Identifier s.a
    Identifier s.a (alias s_a)
    Identifier y.a
    Identifier y.a (alias y_a)
   TablesInSelectQuery (children 3)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier t
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier s
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier t.a
        Identifier s.a
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier y
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier y.b
        Identifier s.b
   ExpressionList (children 3)
    OrderByElement (children 1)
     Identifier t.a
    OrderByElement (children 1)
     Identifier s.a
    OrderByElement (children 1)
     Identifier y.a
