PHP数据库操作
连接MySQL数据库
使用MySQLi扩展连接数据库：
<?php
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "mydb";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
die("连接失败: " . $conn->connect_error);
}
echo "连接成功";
?>查询数据
执行SELECT查询并获取结果：
<?php
$sql = "SELECT id, name, email FROM users";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
while($row = $result->fetch_assoc()) {
echo "ID: " . $row["id"] . " - 姓名: " . $row["name"];
}
} else {
echo "0 结果";
}
?>插入数据
向数据库插入新记录：
<?php
$sql = "INSERT INTO users (name, email) VALUES ('李四', 'lisi@example.com')";
if ($conn->query($sql) === TRUE) {
echo "新记录插入成功";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
?>预处理语句
使用预处理语句防止SQL注入：
<?php
$stmt = $conn->prepare("INSERT INTO users (name, email) VALUES (?, ?)");
$stmt->bind_param("ss", $name, $email);
$name = "王五";
$email = "wangwu@example.com";
$stmt->execute();
$stmt->close();
$conn->close();
?>