How to roll back used functions in a web service? should I use transaction?

I'm developing a web application that connects to a web service. web service gives me two separate functions but they are related each other. RegisterWorker function register a worker and generate a code for him/her. InsertWorkerInformation function, Inserts some worker information in data base according to generated code.
function int RegisterWorker(parameters)
{
  return Genereated worker code;
}

function int InsertWorkerInformation(int generated worker code)
{
   return 1;//If Success Insert information in DB
   return 0;//If fails
}
My web application receives required information which is filled by user and the first calls theRegisterWorker function and then calls the InsertWorkerInformation function.
int code=Re ...