php如何更新mysql数据库

$conn = mysqli_connect('localhost', 'username', 'password', 'database');

UPDATE table_name SET column1=value1, column2=value2, ... WHERE condition;

$sql = "UPDATE users SET name='John', age=30 WHERE id=1";
$result = mysqli_query($conn, $sql);

<?php
$conn = mysqli_connect('localhost', 'username', 'password', 'database');

if (!$conn) {
    die("连接数据库失败: " . mysqli_connect_error());
}

$sql = "UPDATE users SET name='John', age=30 WHERE id=1";
$result = mysqli_query($conn, $sql);

if ($result) {
    echo "更新成功";
} else {
    echo "更新失败";
}

mysqli_close($conn);
?>