mysql c api test code

mysql.c

/* Simple C program that connects to MySQL Database server
*
* compile with $(mysql_config --cflags) mysql-c-api.c $(mysql_config --libs)
*dependencies: libmysql-dev mysql-client 
*/

#include <mysql.h>
#include <stdio.h>
#include <string.h>
#include <time.h>



main() {
   //date and time variables
   time_t t = time(NULL);
   struct tm tm = *localtime(&t);
   char currentDate[10];
   char currentTime[8];

   MYSQL *conn;
   MYSQL_RES *res;
   MYSQL_ROW row;
   char *server = "localhost";
   char *user = "testuser";
   char *password = "123456"; /* set me first */
   char *database = "test";

   conn = mysql_init(NULL);

   /* Connect to database */

   if (!mysql_real_connect(conn, server,
         user, password, database, 0, NULL, 0)) {
      fprintf(stderr, "%s\n", mysql_error(conn));
      //exit(1);
   }
   printf("build query\n");

   sprintf(currentDate, "%04d.%02d.%02d",tm.tm_year + 1900, tm.tm_mon+1, tm.tm_mday);

   sprintf(currentTime, "%02d:%02d:%02d", tm.tm_hour, tm.tm_min, tm.tm_sec);

   char *card_no = "222";

   char st[250]; //= "INSERT INTO door_control(id,card_no,date,time) VALUES(4, '%s','%s','%s')";

   sprintf(st,"INSERT INTO door_control(id,card_no,date,time) VALUES(7, '%s','%s','%s')",card_no,currentDate,currentTime);

   int st_len = strlen(st);



   //char query[st_l];

   //int len = snprintf(query,st_len + strlen(card_no) , st, chunk);
   printf("sql query:\n%s\n----------\n",st);

   int len = strlen(st);

   if (mysql_real_query(conn, st, len)){
     //finish_with_error(conn);
     fprintf(stderr, "%s\n", mysql_error(conn));
   }

   /* send SQL query */
   if (mysql_query(conn, "SELECT * from door_control")) { //show tables
      fprintf(stderr, "%s\n", mysql_error(conn));
      //exit(1);
   }
   res = mysql_use_result(conn);

   /* output table name */
   printf("door control table data:\n");
   while ((row = mysql_fetch_row(res)) != NULL){

      printf("%s %s %s %s \n", row[0],row[1],row[2],row[3]);

   }
   /* close connection */
   mysql_free_result(res);
   mysql_close(conn);
}