SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function arrayElement (children 1)
     ExpressionList (children 2)
      Literal Array_[UInt64_1, UInt64_2, UInt64_3]
      Function toInt8 (children 1)
       ExpressionList (children 1)
        Literal UInt64_1