SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 3)
    Identifier k
    Identifier a
    Identifier b
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 3)
          ExpressionList (children 2)
           Identifier number (alias k)
           Function toString (alias a) (children 1)
            ExpressionList (children 1)
             Identifier number
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier system.numbers
          Literal UInt64_10
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 4)
          ExpressionList (children 2)
           Identifier number (alias k)
           Function toString (alias b) (children 1)
            ExpressionList (children 1)
             Identifier number
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier system.numbers
          Literal UInt64_5
          Literal UInt64_10
     TableJoin (children 1)
      ExpressionList (children 1)
       Identifier k
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier k