如何通过PHP进行Oracle数据库的事务处理

<?php
$oracle_username = "your_username";
$oracle_password = "your_password";
$oracle_host = "localhost";
$oracle_port = "1521";
$oracle_sid = "your_sid";

$connection_string = "(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=$oracle_host)(PORT=$oracle_port))(CONNECT_DATA=(SID=$oracle_sid)))";
$conn = oci_connect($oracle_username, $oracle_password, $connection_string);

if (!$conn) {
    $e = oci_error();
    trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR);
    exit;
}
?>

<?php
$stid = oci_parse($conn, 'BEGIN
                          DBMS_TRANSACTION.BEGIN;
                        END;');
oci_execute($stid);
?>

<?php
$stid = oci_parse($conn, 'INSERT INTO employees (first_name, last_name) VALUES (:first_name, :last_name)');
$first_name = 'John';
$last_name = 'Doe';

oci_bind_by_name($stid, ':first_name', $first_name);
oci_bind_by_name($stid, ':last_name', $last_name);

oci_execute($stid);

// 进行其他SQL操作...
?>

<?php
$stid = oci_parse($conn, 'COMMIT');
oci_execute($stid);
?>

<?php
$stid = oci_parse($conn, 'ROLLBACK');
oci_execute($stid);
?>

<?php
oci_close($conn);
?>