MySQL cpp

MySQL

MySQL is the most popular open source database management system that is written in c++. It supports various workloads and cloud providers.

Oct 07, 2024

Install MySQL

Go to mysql homepage, download and install mysql:

https://dev.mysql.com/downloads

After installing, you should have mysql root password configured, the installing process might have guided you to set one, otherwise set it by youself.

For example, Kubuntu:
(Kubuntu is a linux desktop operating system written in c++ qt (kubuntu.org)) .

$ su
# apt install ./mysql-XXX-YYY.deb	# It will guide you to set something on installing process.
# apt update
# apt install mysql-server
# systemctl status mysql	# Check if mysql is started

Explore databases with mysql

Explore data with mysql command and sql commands.

$ mysql -u root -p
mysql>
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+

mysql> use mysql
Database changed
mysql> show tables;
mysql> select * from db;
mysql> select * from user;

Create database, table, insert records

Create database

mysql> create database cpp_info;
mysql> use cpp_info
Database changed

Create table

mysql> create table cpp_info
    -> (
    -> id int unsigned key auto_increment,
    -> name varchar(160)
    -> );

Insert info

mysql> insert into cpp_info(name) values
    -> ('cpp'),
    -> ('c++'),
    -> ('boost');

Query

mysql> select * from cpp_info;
+----+-------+
| id | name  |
+----+-------+
|  1 | cpp   |
|  2 | c++   |
|  3 | boost |
+----+-------+

Connect mysql with cpp boost

Connect mysql with c++ boost boost::mysql.
(boost::mysql is c++ mysql client library. (boost::mysql home)) .

Install boost

Install c++ boost libraries first.

Connect mysql with boost::mysql

Connect, query mysql with c++ boost::mysql.

c++ code, save as cpp-mysql.cpp :

#include <boost/mysql.hpp>
#include <iostream>

namespace mysql = boost::mysql;
namespace asio = boost::asio;

using std::string_literals::operator""s;

int main(int argc, char * argv[])
try
{
	if (argc != 4)
		throw std::runtime_error{""s + argv[0] + " <username> <password> <mysql host>"};

	auto ctx = asio::io_context{};
	auto ssl_ctx = asio::ssl::context{asio::ssl::context::tls_client};
	auto conn = mysql::tcp_ssl_connection{ctx.get_executor(), ssl_ctx};
	auto resolver = asio::ip::tcp::resolver{ctx.get_executor()};
	auto ep = resolver.resolve(argv[3], mysql::default_port_string);
	auto params = mysql::handshake_params(
		argv[1],	// username
		argv[2],	// password
		"cpp_info"	// database
	);

	conn.connect(*ep.begin(), params);

	mysql::results results;

	conn.execute("select * from cpp_info", results);

	std::cout << results.rows()[0][1] << std::endl;	// cpp

	for (const auto & row: results.rows())
	{
		std::cout << "=>\t";
		for (const auto & column: row)
		{
			std::cout << column << "\t";
		}
		std::cout << std::endl;
	}

	conn.close();
}
catch (const std::exception & e)
{
	std::cerr << "[c++ exception], ERROR: " << e.what() << std::endl;
	return 1;
}

Compile it:

$ g++ cpp-mysql.cpp -std=c++23 -lssl -lcrypto -lboost_charconv -o cpp-mysql

(c++ Botan TLS)

Run program:

$ ./cpp-mysql
[c++ exception], ERROR: ./cpp-mysql <username> <password> <mysql host>
$ ./cpp-mysql root your-mysql-password localhost
cpp
=>	1	cpp
=>	2	c++
=>	3	boost