SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 8)
    Function toDateTime (alias x) (children 1)
     ExpressionList (children 1)
      Literal \'2010-01-02 03:04:05\'
    Function toDateTime (alias y) (children 1)
     ExpressionList (children 1)
      Literal \'2011-02-03 04:05:06\'
    Function least (children 1)
     ExpressionList (children 2)
      Identifier x
      Identifier y
    Function greatest (children 1)
     ExpressionList (children 2)
      Identifier x
      Identifier y
    Function least (children 1)
     ExpressionList (children 2)
      Identifier x
      Function materialize (children 1)
       ExpressionList (children 1)
        Identifier y
    Function greatest (children 1)
     ExpressionList (children 2)
      Function materialize (children 1)
       ExpressionList (children 1)
        Identifier x
      Identifier y
    Function greatest (children 1)
     ExpressionList (children 2)
      Function materialize (children 1)
       ExpressionList (children 1)
        Identifier x
      Function materialize (children 1)
       ExpressionList (children 1)
        Identifier y
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Function least (children 1)
       ExpressionList (children 2)
        Identifier x
        Identifier y