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PHP MySQL 更新数据



使用MySQLi 和 PDO更新MySQL表数据

UPDATE 语句用于中修改数据库表中的数据。

UPDATE table_name
SET column1=value, column2=value2,...
WHERE some_column=some_value 
Note 注意 UPDATE 语法中的 WHERE 子句: WHERE 子句规定了哪些记录需要更新。如果您想省去 WHERE 子句,所有的记录都会被更新!

如需学习更多关于 SQL 的知识,请访问我们的 SQL 教程

让我们看看 "MyGuests" 表:

id firstname lastname email reg_date
1 John Doe john@example.com 2014-10-22 14:26:15
2 Mary Moe mary@example.com 2014-10-23 10:22:30

下面实例更新 "MyGuests" 表 id=2 的记录:

Example (MySQLi 面向对象)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// 创建数据库连接
$conn = new mysqli($servername, $username, $password, $dbname);
// 检查数据库连接
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

$sql = "UPDATE MyGuests SET lastname='Doe' WHERE id=2";

if ($conn->query($sql) === TRUE) {
    echo "Record updated successfully";
} else {
    echo "Error updating record: " . $conn->error;
}

$conn->close();
?>

Example (MySQLi 面向过程)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// 创建数据库连接
$conn = mysqli_connect($servername, $username, $password, $dbname);
// 检查数据库连接
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

$sql = "UPDATE MyGuests SET lastname='Doe' WHERE id=2";

if (mysqli_query($conn, $sql)) {
    echo "Record updated successfully";
} else {
    echo "Error updating record: " . mysqli_error($conn);
}

mysqli_close($conn);
?>

Example (PDO)

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDBPDO";

try {
    $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
    // 设置 PDO 错误模式,用于抛出异常
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    $sql = "UPDATE MyGuests SET lastname='Doe' WHERE id=2";

    // 预处理语句
    $stmt = $conn->prepare($sql);

    // 执行查询
    $stmt->execute();

    // 输出更新成功的消息提示
    echo $stmt->rowCount() . " records UPDATED successfully";
    }
catch(PDOException $e)
    {
    echo $sql . "<br>" . $e->getMessage();
    }

$conn = null;
?>

更新完数据后,表中的数据如下:

id firstname lastname email reg_date
1 John Doe john@example.com 2014-10-22 14:26:15
2 Mary Doe mary@example.com 2014-10-23 10:22:30