SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function equals (children 1)
     ExpressionList (children 2)
      Function URLHash (children 1)
       ExpressionList (children 2)
        Literal \'http://ya.ru/a\' (alias url)
        Literal UInt64_0 (alias level)
      Function URLHash (children 1)
       ExpressionList (children 1)
        Function arrayElement (children 1)
         ExpressionList (children 2)
          Function URLHierarchy (children 1)
           ExpressionList (children 1)
            Identifier url
          Function plus (children 1)
           ExpressionList (children 2)
            Identifier level
            Literal UInt64_1