Benchmark(int argc, char** argv) : res(argc,argv) {
      // response headers
      res.set_content_type("application/json");

      // create prepared statement
      stmt = mysql_stmt_init(db.connection());
      static const char* sql="SELECT randomNumber FROM World WHERE id = ?";
      mysql_stmt_prepare(stmt,sql,strlen(sql));

      ustmt = mysql_stmt_init(db.connection());
      static const char* usql="UPDATE World SET randomNumber = ? WHERE id = ?";
      mysql_stmt_prepare(ustmt,usql,strlen(usql));
    }
 Benchmark(int argc,char** argv) : res(argc,argv) {
   res.set_content_type("application/json");
 }