深入理解MySQL中的事务机制

CREATE TABLE `employee` (
 `id` int NOT NULL AUTO_INCREMENT,
 `first_name` varchar(100) NOT NULL,
 `last_name` varchar(100) NOT NULL,
 `job_title` varchar(100) DEFAULT NULL,
 `salary` double DEFAULT NULL,
 `notes` text,
 PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `employee` (`first_name`, `last_name`, `job_title`, `salary`) VALUES
            ('Robin', 'Jackman', 'Software Engineer', 5500),
            ('Taylor', 'Edward', 'Software Architect', 7200),
            ('Vivian', 'Dickens', 'Database Administrator', 6000),
            ('Harry', 'Clifford', 'Database Administrator', 6800),
            ('Eliza', 'Clifford', 'Software Engineer', 4750),
            ('Nancy', 'Newman', 'Software Engineer', 5100),
            ('Melinda', 'Clifford', 'Project Manager', 8500),
            ('Harley', 'Gilbert', 'Software Architect', 8000);

CREATE TABLE `telephone` (
 `id` int NOT NULL AUTO_INCREMENT,
 `employee_id` int DEFAULT NULL,
 `type` varchar(20) NOT NULL,
 `no` varchar(50) NOT NULL,
 PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `telephone` (`employee_id`, `type`, `no`) VALUES
            (1, 'mobile',  '245-249697'),
            (2, 'mobile',  '270-235969'),
            (2, 'land',   '325-888885'),
            (3, 'mobile',  '270-684972'),
            (4, 'mobile',  '245-782365'),           
            (4, 'land',   '325-888886'),
            (5, 'mobile',  '245-537891'),
            (6, 'mobile',  '270-359457'),
            (7, 'mobile',  '245-436589'),                           
            (7, 'land',   '325-888887'),
            (8, 'mobile',  '245-279164'),                           
            (8, 'land',   '325-888888');

INSERT INTO `employee` (`id`, `first_name`, `last_name`,
`job_title`, `salary`) VALUES (9, 'Grace', 'Williams',
'Softwaree Engineer', 5000);
 
INSERT INTO `telephone` (`id`, `employee_id`, `type`,
`no`) VALUES (13, 9, 'mobile', '270-598712');

<?php
 
//$salary = 5000;
$salary = '$5000';
 
/* Change database details according to your database */
$dbConnection = mysqli_connect('localhost', 'robin', 'robin123', 'company_db');
 
mysqli_autocommit($dbConnection, false);
 
$flag = true;
 
$query1 = "INSERT INTO `employee` (`id`, `first_name`, `last_name`, `job_title`, `salary`) VALUES (9, 'Grace', 'Williams', 'Softwaree Engineer', $salary)";
$query2 = "INSERT INTO `telephone` (`id`, `employee_id`, `type`, `no`) VALUES (13, 9, 'mobile', '270-598712')";
 
$result = mysqli_query($dbConnection, $query1);
 
if (!$result) {
  $flag = false;
  echo "Error details: " . mysqli_error($dbConnection) . ". ";
}
 
$result = mysqli_query($dbConnection, $query2);
 
if (!$result) {
  $flag = false;
  echo "Error details: " . mysqli_error($dbConnection) . ". ";
}
 
if ($flag) {
 
  mysqli_commit($dbConnection);
  echo "All queries were executed successfully";
 
} else {
 
  mysqli_rollback($dbConnection);
  echo "All queries were rolled back"; 
 
}
 
mysqli_close($dbConnection);
 
?>