basic help with c++ connector 8.0.23 :-(

Heya,

here is an update on an somewhat older topic

It looks like you’re on the right track with your C++ MySQL connector! You might need to adjust your approach slightly, though. Here are a few things to consider:

1. Exception Handling: In your catch statement, you’re catching an exception by value, which can lead to object slicing and loss of data. Instead, catch by reference:

catch(const std::exception& e){
    std::cout << e.what() << std::endl;
    return 1;
}

2. Credentials: Verify that your MySQL credentials (username, password) and connection details (host, port) are correct. If your MySQL server is not on the same machine where you’re running this program, ensure that it’s configured to accept connections from your client’s IP address. In your case, since you are using the IP address for the host, make sure that MySQL is not bound to localhost (127.0.0.1) but to 0.0.0.0 or your specific IP address.

3. Firewall: Ensure there are no firewall rules preventing you from connecting to the MySQL port (3306 by default) on your server.

4. Test Connection: Try to connect to your MySQL database from your command line, using mysql -h <host> -u <username> -p<password> -D <database>. This can help you determine if the issue is with your program or with your server setup.

5. SSH Tunnel: You’ve mentioned that you log into your droplet via SSH. If your MySQL server only accepts local connections (which is common for security reasons), you’d have to create an SSH tunnel before connecting with your C++ code. You’d then connect to ‘localhost’ in your C++ code, but that connection would actually be tunneled through SSH to your remote MySQL server.

If your database is bound to localhost (for security reasons), you can’t access it directly from an external IP address. Instead, you would access it through an SSH tunnel. This is likely the reason you’re able to access it through PHP (the PHP code is running on the droplet and can access the database locally), but not from your C++ code running on a different machine.

Creating an SSH tunnel involves using the ssh command with the -L option, which forwards a local port to a port on the remote machine. This would be done from the machine where your C++ code is running.

The command might look something like this:

ssh -L 3306:localhost:3306 username@droplet_ip

This command opens an SSH connection to your droplet, and also forwards any connections to port 3306 on the local machine to port 3306 on the droplet. You can then modify your C++ code to connect to ‘localhost’ instead of the IP of your droplet.

However, this requires your C++ program to have the ability to create and manage an SSH connection, which is likely beyond its current capabilities. Instead, you might consider running your C++ code on the droplet, or exploring other ways to allow external connections to your MySQL server (such as modifying its bind address or firewall rules). Always ensure that you’re following security best practices when modifying server configurations.

Remember to replace "localhost" with the IP of your MySQL server in your C++ code, and username@droplet_ip with your SSH username and the IP address of your droplet in the SSH command.

Please note that the approach of SSH tunnel is not the most suitable for a production environment, but it’s OK for testing or development. For production environments, consider a more secure approach such as a VPN, or adjusting your MySQL server to accept secure external connections.