SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Function parseDateTimeBestEffortOrNull (alias a) (children 1)
     ExpressionList (children 2)
      Literal \'<Empty>\'
      Literal UInt64_3
    Function toTypeName (children 1)
     ExpressionList (children 1)
      Identifier a
