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//
// Copyright (c) 2019-2025 Ruben Perez Hidalgo (rubenperez038 at gmail dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include <boost/asio/awaitable.hpp>
#ifdef BOOST_ASIO_HAS_CO_AWAIT
//[example_inserts
/**
* This example demonstrates how to use INSERT statements,
* the results::last_insert_id() function, and optionals
* to represent potentially NULL values.
*
* The program inserts an employee, given their first name,
* last name and company ID. It then prints the ID of the newly
* inserted employee.
*
* It uses C++20 coroutines. If you need, you can backport
* it to C++11 by using callbacks, asio::yield_context
* or sync functions instead of coroutines.
*
* This example uses the 'boost_mysql_examples' database, which you
* can get by running db_setup.sql.
*/
#include <boost/mysql/any_connection.hpp>
#include <boost/mysql/error_with_diagnostics.hpp>
#include <boost/mysql/results.hpp>
#include <boost/mysql/with_params.hpp>
#include <boost/asio/awaitable.hpp>
#include <boost/asio/co_spawn.hpp>
#include <boost/asio/io_context.hpp>
#include <cstdint>
#include <iostream>
#include <optional>
#include <string>
#include <string_view>
namespace mysql = boost::mysql;
namespace asio = boost::asio;
// The main coroutine
asio::awaitable<void> coro_main(
std::string_view server_hostname,
std::string_view username,
std::string_view password,
std::string_view first_name,
std::string_view last_name,
std::string_view company_id,
std::optional<std::uint32_t> salary // empty optional means that a NULL value should be inserted
)
{
// Create a connection.
// Will use the same executor as the coroutine.
mysql::any_connection conn(co_await asio::this_coro::executor);
// The server host, username, password and database to use.
mysql::connect_params params;
params.server_address.emplace_host_and_port(std::string(server_hostname));
params.username = std::move(username);
params.password = std::move(password);
params.database = "boost_mysql_examples";
// Connect to the server
co_await conn.async_connect(params);
// Perform the insertion.
// If salary is empty, the last {} will be replaced by NULL.
mysql::results result;
co_await conn.async_execute(
mysql::with_params(
"INSERT INTO employee (first_name, last_name, company_id, salary) VALUES ({}, {}, {}, {})",
first_name,
last_name,
company_id,
salary
),
result
);
// results::last_insert_id retrieves the value of the latest
// AUTO_INCREMENT field generated by the executed query, if any.
// In this case, this is the generated employee_id.
// If we needed the entire generated employee, we'd need a transaction
// and multi-queries.
std::cout << "Successfully created employee with ID: " << result.last_insert_id() << std::endl;
// Notify the MySQL server we want to quit, then close the underlying connection.
co_await conn.async_close();
}
void main_impl(int argc, char** argv)
{
if (argc < 7 || argc > 8)
{
std::cerr
<< "Usage: " << argv[0]
<< " <username> <password> <server-hostname> <first-name> <last-name> <company-id> [<salary>]\n";
exit(1);
}
// In DB, salary is an UNSIGNED INT (32-bit) representing employee salary in USD
// It may be NULL (e.g. for contractors).
// Parse the command line argument, if present, and validate it's within a sane range
std::optional<std::uint32_t> salary;
if (argc == 8)
{
int parsed_salary = std::stoi(argv[7]);
if (parsed_salary < 10000 || parsed_salary >= 1000000)
{
std::cerr << "Salary should be between 10000 and 1000000\n";
exit(1);
}
salary = static_cast<std::uint32_t>(parsed_salary);
}
// Create an I/O context, required by all I/O objects
asio::io_context ctx;
// Launch our coroutine
asio::co_spawn(
ctx,
[=] { return coro_main(argv[3], argv[1], argv[2], argv[4], argv[5], argv[6], salary); },
// If any exception is thrown in the coroutine body, rethrow it.
[](std::exception_ptr ptr) {
if (ptr)
{
std::rethrow_exception(ptr);
}
}
);
// Calling run will actually execute the coroutine until completion
ctx.run();
std::cout << "Done\n";
}
int main(int argc, char** argv)
{
try
{
main_impl(argc, argv);
}
catch (const boost::mysql::error_with_diagnostics& err)
{
// Some errors include additional diagnostics, like server-provided error messages.
// Security note: diagnostics::server_message may contain user-supplied values (e.g. the
// field value that caused the error) and is encoded using to the connection's character set
// (UTF-8 by default). Treat is as untrusted input.
std::cerr << "Error: " << err.what() << ", error code: " << err.code() << '\n'
<< "Server diagnostics: " << err.get_diagnostics().server_message() << std::endl;
return 1;
}
catch (const std::exception& err)
{
std::cerr << "Error: " << err.what() << std::endl;
return 1;
}
}
//]
#else
#include <iostream>
int main()
{
std::cout << "Sorry, your compiler doesn't have the required capabilities to run this example"
<< std::endl;
}
#endif
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