php ，MySQL操作的两种方式

本文省略php对MySQL的面向过程的操作方式，介绍最常用的，面向对象的操作方式和PDO方式

面向对象的操作方式：

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

// 创建连接
$conn = new mysqli($servername, $username, $password);

// 确定数据库，创建连接
//$conn = new mysqli($servername, $username, $password, $dbname);
// 检测连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 创建数据库
$sql = "CREATE DATABASE myDB";
if ($conn->query($sql) === TRUE) {
    echo "数据库创建成功";
} else {
    echo "Error creating database: " . $conn->error;
}

//选择数据库

mysql_select_db( 'MyDB' );

// 使用 sql 创建数据表

	$sql 
	= "CREATE TABLE MyGuests (
id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY 
	KEY, 
firstname VARCHAR(30) NOT NULL,
lastname VARCHAR(30) NOT NULL,
email 
	VARCHAR(50),
reg_date TIMESTAMP
)";

	
if ($conn->query($sql) === TRUE) {
    echo "Table 
	MyGuests created successfully";
} else {
    echo 
	"创建数据表错误: " . $conn->error;
}

//插入数据
$sql = "INSERT INTO MyGuests (firstname, lastname, email)

	VALUES ('John', 'Doe', 'john@example.com')";

	
if ($conn->query($sql) === TRUE) {
    echo "新记录插入成功";
} else {
    echo 
	"Error: " . $sql . "<br>" . $conn->error;
}
//插入多条数据
$sql = "INSERT INTO MyGuests (firstname, lastname, email)

	VALUES ('John', 'Doe', 'john@example.com');";

	$sql .= "INSERT INTO 
	MyGuests (firstname, lastname, email)

	VALUES ('Mary', 'Moe', 'mary@example.com');";

	$sql .= "INSERT INTO 
	MyGuests (firstname, lastname, email)

	VALUES ('Julie', 'Dooley', 'julie@example.com')";

	
if ($conn->multi_query($sql) === TRUE) {
    echo "新记录插入成功";
} else {
    echo 
	"Error: " . $sql . "<br>" . $conn->error;
}


// 预处理及绑定
$stmt = $conn->prepare("INSERT INTO MyGuests (firstname, lastname, email) 
	VALUES(?, ?, ?)");
$stmt->bind_param("sss", $firstname, $lastname, 
	$email);

// 设置参数并执行
$firstname = "John";
$lastname 
	= "Doe";
$email = "john@example.com";
$stmt->execute();

$firstname 
	= "Mary";
$lastname = "Moe";
$email = "mary@example.com";
$stmt->execute();

	
$firstname = "Julie";
$lastname = "Dooley";
$email = "julie@example.com";

	$stmt->execute();

echo "新记录插入成功";

$stmt->close();


//读取数据
$sql = "SELECT id, firstname, lastname FROM MyGuests";
$result 
	= $conn->query($sql);

if ($result->num_rows > 0) {
    
	// 输出每行数据
    while($row = $result->fetch_assoc()) 
	{
        echo "<br> id: ". 
	$row["id"]. " - Name: ". $row["firstname"]. " " . $row["lastname"];
    
	}
} else {
    echo "0 个结果";
}

$conn->close();
?>

 

使用pdo方式

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

try {
    $conn = new PDO("mysql:host=$servername;dbname=myDB", $username, $password);

    // 设置 PDO 错误模式为异常
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    $sql = "CREATE DATABASE myDBPDO";

    // 使用 exec() ，因为没有结果返回
    $conn->exec($sql);

    echo "数据库创建成功<br>";

　　    // 使用 sql 创建数据表
    $sql = "CREATE TABLE MyGuests (
    id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    firstname VARCHAR(30) NOT NULL,
    lastname VARCHAR(30) NOT NULL,
    email VARCHAR(50),
    reg_date TIMESTAMP
    )";
    // 使用 exec() ，没有结果返回
    $conn->exec($sql);
    echo "数据表 MyGuests 创建成功";

//插入数据

    $sql = "INSERT INTO MyGuests (firstname, lastname, email)
    VALUES ('John', 'Doe', 'john@example.com')";
    // 使用 exec() ，没有结果返回
    $conn->exec($sql);
    echo "新记录插入成功";

//插入多条数据

    // 开始事务
    $conn->beginTransaction();
    // SQL 语句
    $conn->exec("INSERT INTO MyGuests (firstname, lastname, email)
    VALUES ('John', 'Doe', 'john@example.com')");
    $conn->exec("INSERT INTO MyGuests (firstname, lastname, email)
    VALUES ('Mary', 'Moe', 'mary@example.com')");
    $conn->exec("INSERT INTO MyGuests (firstname, lastname, email)
    VALUES ('Julie', 'Dooley', 'julie@example.com')");

    // 提交事务
    $conn->commit();
    echo "新记录插入成功";

 

 

 

// 预处理 SQL 并绑定参数
    $stmt = $conn->prepare("INSERT INTO MyGuests (firstname, lastname, email)
    VALUES (:firstname, :lastname, :email)");
    $stmt->bindParam(':firstname', $firstname);
    $stmt->bindParam(':lastname', $lastname);
    $stmt->bindParam(':email', $email);

    // 插入行
    $firstname = "John";
    $lastname = "Doe";
    $email = "john@example.com";
    $stmt->execute();

    // 插入其他行
    $firstname = "Mary";
    $lastname = "Moe";
    $email = "mary@example.com";
    $stmt->execute();

    // 插入其他行
    $firstname = "Julie";
    $lastname = "Dooley";
    $email = "julie@example.com";
    $stmt->execute();

    echo "新记录插入成功";

 

//查询数据

  $stmt = $conn->prepare("SELECT * FROM MyGuests");
    $stmt->execute();

    // 设置结果集为关联数组
    $result = $stmt->setFetchMode(PDO::FETCH_ASSOC);

    foreach(new TableRows(new RecursiveArrayIterator($stmt->fetchAll())) as $k=>$v) {
        echo $v;
    }
    $stmt = null;
}
catch(PDOException $e)
{
    echo $sql . "<br>" . $e->getMessage();
}

$conn = null;
?>