mysql problem

From: Alfredo (alfredo_at_econtact.se)
Date: 09/23/04

  • Next message: Paul: "Re: calling fopen using function" 
    Date: Thu, 23 Sep 2004 13:17:23 GMT

    Hello everybody

    I got a strange problem when retrieving data from a sql query. I have a
    function that queries the database, gets data and store that in a struct. I
    hope ist ok to post all the code:

    ADINFO getRefPhone(char * ref){
         ADINFO retInfo;
         char * sqlQuery[100];
         unsigned int num_fields;
         MYSQL * conn;
         MYSQL_RES * res;
         MYSQL_FIELD * fd;
         MYSQL_ROW row;
         conn = mysql_init((MYSQL*) 0);
         memset(&retInfo, 0, sizeof(retInfo));

         if (conn!=NULL){
             mysql_real_connect(conn, "0.0.0.0", "root", "", NULL, MYSQL_PORT,
    NULL, 0);//the real ipnumber is not shown
             if (conn!=NULL){
                mysql_select_db(conn, "dbname");
                strcpy(sqlQuery, "SELECT phone, user_id FROM reference WHERE
    reference_id=");
                strcat(sqlQuery, ref);
                if (mysql_query(conn, sqlQuery)){
                 res = mysql_store_result(conn);
                   //HERE IS THE PROBLEM
                    if (res){
                        printf("resisok\n\r");
                        row = mysql_fetch_row(res);
                        if(row){
                            printf("rowisok\n\r");
                            strcpy(retInfo.phone, row[0]);
                        strcpy(retInfo.userid, row[1]);
                         }
                         else{
                          printf("rowisnotok\n\r");
                         }
                     }
                     else{
                      printf("resisnotok\n\r");
                     }
               }
               else{
                printf("mysqlquereynotok\n\r");
               }
               mysql_close(conn);
            }
            else{
             printf("connisnull\n\r");
            }
         }
         else{
          printf("connisnull\n\r");
         }
         return retInfo;
    }

    Everything works ok until I do
    res = mysql_store_result(conn);

    if (res)

    Thus, res becomes null. Why?

    The connection is ok. The query ( I printed it and it looks ok) too. The
    char *ref contains the right value. I tried to print it put. eg. I got the
    value 1010. I checked in the database and that value was actually stored in
    the database. So please, why is res null?

    Regards Alfredo

  • Next message: Paul: "Re: calling fopen using function"

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