SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 2)
    Function count (children 1)
     ExpressionList (children 1)
      Function _CAST (children 1)
       ExpressionList (children 2)
        Literal NULL
        Literal \'Nullable(Nothing)\'
    Function round (alias k) (children 1)
     ExpressionList (children 1)
      Function avg (children 1)
       ExpressionList (children 1)
        Function _CAST (children 1)
         ExpressionList (children 2)
          Literal NULL
          Literal \'Nullable(Nothing)\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Function numbers (children 1)
       ExpressionList (children 1)
        Literal UInt64_256
   Set
