php实现mysql
PHP 连接 MySQL 的基本方法
使用 mysqli 扩展连接 MySQL 数据库。确保 PHP 已安装 mysqli 扩展,MySQL 服务正常运行。
<?php
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "myDB";
// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);
// 检查连接
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
echo "Connected successfully";
?>
执行 SQL 查询
通过 query 方法执行 SQL 语句,处理查询结果。
$sql = "SELECT id, name FROM users";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
echo "id: " . $row["id"]. " - Name: " . $row["name"]. "<br>";
}
} else {
echo "0 results";
}
插入数据到 MySQL
使用预处理语句防止 SQL 注入,插入数据更安全。

$stmt = $conn->prepare("INSERT INTO users (name, email) VALUES (?, ?)");
$stmt->bind_param("ss", $name, $email);
$name = "John Doe";
$email = "john@example.com";
$stmt->execute();
echo "New records created successfully";
$stmt->close();
更新 MySQL 数据
通过预处理语句更新现有记录。
$stmt = $conn->prepare("UPDATE users SET name=? WHERE id=?");
$stmt->bind_param("si", $name, $id);
$name = "Jane Doe";
$id = 1;
$stmt->execute();
echo "Record updated successfully";
$stmt->close();
关闭数据库连接
操作完成后关闭连接释放资源。

$conn->close();
错误处理
使用 try-catch 块捕获异常,提高代码健壮性。
try {
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
throw new Exception("Connection failed: " . $conn->connect_error);
}
} catch (Exception $e) {
echo "Error: " . $e->getMessage();
}
使用 PDO 连接 MySQL
PDO 提供统一的接口支持多种数据库,更灵活。
try {
$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
echo "Connected successfully";
} catch(PDOException $e) {
echo "Connection failed: " . $e->getMessage();
}






