c# - OleDB update command not changing data -

i'm using microsoft access file database. have no problem select , insert queries when try update, record in database not change.

below code use run update. there no exceptions or errors in debug log.

    cnn = new oledbconnection(connetionstring);      oledbcommand command = new oledbcommand("update [wpisy] set [wpis]=@wpis, [id_kat]=@id_kat, [tytul]=@tytul [id]=@id_wpis" , cnn);     command.parameters.add(new oledbparameter("@wpis", tresc_wpisu.text));     command.parameters.add(new oledbparameter("@id_kat", lista_kategorii.selectedvalue));     command.parameters.add(new oledbparameter("@tytul", tytul_wpisu.text));     command.parameters.add(new oledbparameter("@id_wpis", request["id"].tostring() ));     command.connection = cnn;      try     {         if(cnn.state.tostring() != "open")         cnn.open();         command.executenonquery();         cnn.close();     }     catch (oledbexception ex)     {         response.clear();         response.write(ex);         response.end();     } 

i go microsoft access , enter command there , see happens. should tell how many rows affected. if says 0 rows, break query smaller pieces, such as:

select * [id]=value

and should able track down problem is.