SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function arrayMax (children 1)
     ExpressionList (children 2)
      Function lambda (children 1)
       ExpressionList (children 2)
        Function tuple (children 1)
         ExpressionList (children 1)
          Identifier x
        Function tupleElement (children 1)
         ExpressionList (children 2)
          Identifier x
          Literal UInt64_1
      Function array (children 1)
       ExpressionList (children 2)
        Literal Tuple_(UInt64_1, \'a\')
        Literal Tuple_(UInt64_0, \'b\')
