bool query(unsigned int ip,string &city,string &country)
{
    char sql[256];
    memset(sql,0,256);
    sprintf_s(sql,256,"select country,city FROM citylocation where LocId = (select LocId from ipindex where                    startIpNum <= %u  and endIpNum >=  %u limit 1)",ip,ip);

    DWORD start,end;
    start = GetTickCount();
    if( mysql_real_query(mysql,sql,strlen(sql)) !=0 )
        return false;                            // 查询失败
    end = GetTickCount();
    cout << end - start << "  "  << endl;           //查询时间

    MYSQL_RES *rs=mysql_store_result(mysql);     
    if(rs != NULL)
    {
        MYSQL_ROW row;
        if((row = mysql_fetch_row(rs)) == NULL)
            return false;
        if(row[0] != NULL)
            country = row[0];
        if(row[1] != NULL)
            city = row[1];
        free_result(rs);
        return true;
    }    
        return false;
}