SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 3)
          ExpressionList (children 2)
           Identifier foo
           Function untuple (alias top) (children 1)
            ExpressionList (children 1)
             Function arrayJoin (children 1)
              ExpressionList (children 1)
               Function topKWeightedMerge (children 2)
                ExpressionList (children 1)
                 Identifier top_items
                ExpressionList (children 3)
                 Literal UInt64_100
                 Literal UInt64_3
                 Literal \'counts\'
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier topk_test
          ExpressionList (children 1)
           Identifier foo
   ExpressionList (children 3)
    OrderByElement (children 1)
     Identifier foo
    OrderByElement (children 1)
     Identifier top.count
    OrderByElement (children 1)
     Identifier top.item
