mysql c++ connector exceptions: Access denied for user 'root'@'localhost' (using password: NO) && MySQL server has gone away -

i trying using mysql c++ connector connect mysql database on local machine.

i installed mysql c++ connector 7.1.1.9 , boost. in c++ ide. included header path , connector library file libmysqlcppconn-static.a project. project compiles fine.

but when try run example connect local database.

try{     sql::mysql::mysql_driver *driver;     sql::connection *con;      driver = sql::mysql::get_mysql_driver_instance();     // tried user root here, got same exception     //con = driver->connect("tcp://127.0.0.1:3306", "root", "password");     con = driver->connect("tcp://127.0.0.1:3306", "user", "password");      delete con; } catch(sql::sqlexception &e) {      // edit1: fix code based on macxx's comments     // access denied exception thrown here.     std::cerr << e.what() << '\n';  } 

an exception
mysql exceptions: access denied user 'root'@'localhost' (using password: no)
thrown. checked mysql installed correctly accessing in terminal:

$ mysql -u root -p enter password: // <---entered "password" here, sure password correct welcome mysql monitor.  commands end ; or \g. mysql connection id 6 server version: 5.7.18-0ubuntu0.16.04.1 (ubuntu)  copyright (c) 2000, 2017, oracle and/or affiliates. rights reserved.  oracle registered trademark of oracle corporation and/or affiliates. other names may trademarks of respective owners.  type 'help;' or '\h' help. type '\c' clear current input statement.  mysql>  

it seems connector ignoring second parameter. tried use structure connectoptionsmap set ['password'] "password". still not working properly.
suggestion fix exception?

---

a little after connection granted: had difficult time using binary libraries (libmysqlcppconn.so / libmysqlcppconn-static.a) downloaded oracle mysql official website. if execute
con->setschema("an_existing_db")
app throws exception: mysql server has gone away;
if use :

sql::statement *st = con->createstatement(); st->execute("use an_existing_db");`  

the app crashes due bad allocation.

eventually, solved problem using packages apt-get (they version of sqlcppconn).
sudo apt-get install libmysqlcppconn-dev changed project file link libraries in /usr/lib/libmysqlcppconn.so , /usr/lib/x86_64-linux-gnu/libmysqlclient.so.

[environment]
ubuntu 16.04.2
mysql 5.7
mysql connector version: 7.1.1.9
mysql connector version: 7.1.1.7
boost 1.58.0
g++ 5.4.0

thanks in advance

rong

in /etc/mysql/my.cnf, there bind-address line. please set to

bind-address = 0.0.0.0

then restart mysql service.

next try execute program.

also while creating mysql database, user make sure permissions proper, can refer below instructions (valid on linux / ubuntu)

create user 'user_user'@'localhost' identified 'user_password'; create user 'user_user'@'%' identified 'user_password'; grant on *.* 'user_user'@'localhost'; grant on *.* 'user_user'@'%';  create database user_database;  grant usage on *.* user_user@'localhost' identified 'user_password'; grant usage on *.* user_user@'%' identified 'user_password';  grant privileges on user_database.* user_user@'localhost' ; grant privileges on user_database.* user_user@'%' ; 

and if writing code on qt, below code works me

    qsqldatabase db;      db = qsqldatabase::adddatabase("qmysql");      db.sethostname(dbhost);     db.setdatabasename(dbname);     db.setusername(dbusername);     db.setpassword(dbpassword);     db.setport(dbport);       if (!db.open())     {         qmessagebox::critical(this,"error","could not connect database.");     }