SELECTクエリで文字列を取得するMySQLC++コネクタ

resから実際のフィールドをフェッチする必要があります 。簡単に拡張できる簡単な例を次に示します。

#include <stdlib.h>
#include <stdio.h>
#include <stdio.h>
#include <iostream>
#include <string>

#include <windows.h>
#include <mysql/mysql.h>

using namespace std;

static char *opt_host_name = "host"; /* HOST */
static char *opt_user_name = "user"; /* USERNAME */
static char *opt_password = "pass"; /* PASSWORD */
static unsigned int opt_port_num = 3306; /* PORT */
static char *opt_socket_name = NULL; /* SOCKET NAME, DO NOT CHANGE */
static char *opt_db_name = "database name"; /* DATABASE NAME */
static unsigned int opt_flags = 0; /* CONNECTION FLAGS, DO NOT CHANGE */

int main ()
{
    MYSQL *conn; /* pointer to connection handler */
    MYSQL_RES *res; /* holds the result set */
    MYSQL_ROW row;



    /* INITIALIZE CONNECTION HANDLER, DO NOT CHANGE */
    conn = mysql_init (NULL);

    /* THIS CONNECTS TO SERVER, DO NOT CHANGE ANYTHING HERE */
    mysql_real_connect (conn, opt_host_name, opt_user_name, opt_password,
    opt_db_name, opt_port_num, opt_socket_name, opt_flags);
    /* show tables in the database (test for errors also) */
    mysql_query(conn, "SELECT Password FROM Users WHERE Name = 'MY_NICKNAME'");
    res = mysql_store_result(conn);


    // get the number of the columns
    int num_fields = mysql_num_fields(res);
    // Fetch all rows from the result
    while ((row = mysql_fetch_row(res)))
    {
       // Print all columns
       for(int i = 0; i < num_fields; i++)
       {
           // Make sure row[i] is valid!
           if(row[i] != NULL)
                cout << row[i] << endl;
           else
                cout << "NULL" << endl;

           // Also, you can use ternary operator here instead of if-else
           // cout << row[i] ? row[i] : "NULL" << endl;
       }
    }

    // DON'T FORGET TO CLEAN RESULT AFTER YOU DON'T NEED IT 
    // ANYMORE

    if(res != NULL)
       mysql_free_result(res);

    /* disconnect from server */
    mysql_close (conn);

    system("pause");
    return 0;
} 
/* end main function */