SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function if (children 1)
     ExpressionList (children 3)
      Function greater (children 1)
       ExpressionList (children 2)
        Function materialize (children 1)
         ExpressionList (children 1)
          Literal UInt64_1
        Literal UInt64_0
      Function materialize (children 1)
       ExpressionList (children 1)
        Function CAST (children 1)
         ExpressionList (children 2)
          Literal UInt64_2
          Literal \'Nullable(Decimal(9, 4))\'
      Function CAST (children 1)
       ExpressionList (children 2)
        Literal NULL
        Literal \'Nullable(Decimal(18, 4))\'
