PHP怎么删除MySQL数据库中的指定数据

<?php
$servername = "localhost";
$username = "your_username";
$password = "your_password";
$dbname = "your_database";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 假设我们要删除id为5的记录
$sql = "DELETE FROM your_table WHERE id = 5";

if ($conn->query($sql) === TRUE) {
    echo "记录已删除成功";
} else {
    echo "错误删除记录: " . $conn->error;
}

$conn->close();
?>

<?php
$conn->autocommit(FALSE);

try {
    $sql1 = "DELETE FROM table1 WHERE condition1";
    $sql2 = "DELETE FROM table2 WHERE condition2";

    if ($conn->query($sql1) === TRUE && $conn->query($sql2) === TRUE) {
        $conn->commit();
        echo "事务完成，记录已删除";
    } else {
        $conn->rollback();
        echo "事务回滚，删除失败";
    }
} catch (Exception $e) {
    $conn->rollback();
    echo "错误: " . $e->getMessage();
}

$conn->close();
?>

<?php
$stmt = $conn->prepare("DELETE FROM your_table WHERE id = ?");
$id = 5;
$stmt->bind_param("i", $id);

if ($stmt->execute()) {
    echo "记录已删除成功";
} else {
    echo "错误删除记录: " . $stmt->error;
}

$stmt->close();
$conn->close();
?>