SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function arraySort (children 1)
     ExpressionList (children 1)
      Function topKWeighted (children 2)
       ExpressionList (children 2)
        Identifier val1
        Identifier val2
       ExpressionList (children 1)
        Literal UInt64_10
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier topk