mysqli常用增删改指令

<?php
$host = 'localhost';
$user = 'username';
$password = 'password';
$dbname = 'database_name';

// 创建连接
$conn = new mysqli($host, $user, $password, $dbname);

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

// 插入数据
$sql = "INSERT INTO table_name (column1, column2, column3) VALUES (?, ?, ?)";
$stmt = $conn->prepare($sql);
$stmt->bind_param("sss", $value1, $value2, $value3);
$value1 = 'value1';
$value2 = 'value2';
$value3 = 'value3';
$stmt->execute();

echo "新记录插入成功";

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

<?php
// ...（连接数据库部分与上面相同）

// 删除数据
$sql = "DELETE FROM table_name WHERE condition = ?";
$stmt = $conn->prepare($sql);
$stmt->bind_param("s", $conditionValue);
$conditionValue = 'some_value';
$stmt->execute();

echo "记录删除成功";

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

<?php
// ...（连接数据库部分与上面相同）

// 更新数据
$sql = "UPDATE table_name SET column1 = ?, column2 = ? WHERE condition = ?";
$stmt = $conn->prepare($sql);
$stmt->bind_param("sss", $newValue1, $newValue2, $conditionValue);
$newValue1 = 'new_value1';
$newValue2 = 'new_value2';
$conditionValue = 'some_value';
$stmt->execute();

echo "记录更新成功";

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