PHP17 PDO

PDO::__construct($dsn, [optional] $username, [optional] $passwd, [optional] $options) 
Creates a PDO instance representing a connection to a database.
Parameters:
$dsn : datasource name. 
[optional] $username  
[optional] $passwd  
[optional] $options  : Param Array. Optimize PDO.

$dsn = ‘mysql:dbname=myschool;host=localhost‘;
$user = ‘root‘;
$password = ‘rootkit‘;
try {
	$pdo = new PDO ( $dsn, $user, $password );
} catch ( PDOException $ex ) {
	echo ‘连接数据库失败：‘ . $ex->getMessage ();
}
if($pdo!=null){
	echo ‘连接数据库成功！‘;
}else{
	echo ‘连接数据库失败！‘;
}

$opt=array(PDO::ATTR_PERSISTENT => TRUE);
try {
	$dbh = new PDO(‘mysql:dbname=myschool;host=localhost‘, ‘root‘, ‘rootkit‘, $opt);
} catch (PDOException $e) {
	echo ‘数据库连接失败：‘.$e->getMessage();
	exit;
}
echo "<br>PDO是否关闭自动提交功能："
.$dbh->getAttribute(PDO::ATTR_AUTOCOMMIT);
echo "<br>当前PDO的错误处理的模式："
.$dbh->getAttribute(PDO::ATTR_ERRMODE);
echo "<br>表字段字符的大小写转换： "
.$dbh->getAttribute(PDO::ATTR_CASE);
echo "<br>与连接状态相关特有信息： "
.$dbh->getAttribute(PDO::ATTR_CONNECTION_STATUS);
echo "<br>空字符串转换为SQL的null："
.$dbh->getAttribute(PDO::ATTR_ORACLE_NULLS);
echo "<br>应用程序提前获取数据大小："
.$dbh->getAttribute(PDO::ATTR_PERSISTENT);
echo "<br>与数据库特有的服务器信息："
.$dbh->getAttribute(PDO::ATTR_SERVER_INFO);
echo "<br>数据库服务器版本号信息："
.$dbh->getAttribute(PDO::ATTR_SERVER_VERSION);
echo "<br>数据库客户端版本号信息："
.$dbh->getAttribute(PDO::ATTR_CLIENT_VERSION);

$pdo->setAttribute(PDO::ATTR_ORACLE_NULLS, true);

$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_WARNING);

$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);

/*
 * 数据库连接优化选项：
 * 1、持久化连接：持久化
 * 2、错误处理模式：抛出异常
 * 3、空字符串转null值：打开
 */
$option = array (
		PDO::ATTR_PERSISTENT => TRUE,
		PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
		PDO::ATTR_ORACLE_NULLS=>true
);

try {
	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	//增删改
	$query="INSERT INTO users VALUES(‘tom‘,‘123‘,‘访客‘)";
	$pdo->exec($query);
} catch ( PDOException $e ) {
	echo ‘数据库操作失败：‘ . $e->getMessage ();
	exit ();
}

/*
 * 数据库连接优化选项：
 * 1、持久化连接：持久化
 * 2、错误处理模式：抛出异常
 * 3、空字符串转null值：打开
 */
$option = array (
		PDO::ATTR_PERSISTENT => TRUE,
		PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
		PDO::ATTR_ORACLE_NULLS=>true
);

try {
	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	//增删改
	//$query="INSERT INTO users VALUES(‘tom‘,‘123‘,‘访客‘)";
	//$pdo->exec($query);
	//查询
	$query="SELECT * FROM users";
	$pdostmt=$pdo->query($query);
	echo "一共{$pdostmt->rowCount()}条记录<br>";
	echo "id,account,pwd,role<br>";
	foreach ($pdostmt as $row){
		echo "{$row[‘id‘]},{$row[‘username‘]},{$row[‘userpassword‘]},{$row[‘userrole‘]}<br>";
	}
} catch ( PDOException $e ) {
	echo ‘数据库操作失败：‘ . $e->getMessage ();
	exit ();
}

$sql="INSERT INTO users VALUES(:username,:userpassword,:userrole)";

$sql="INSERT INTO users VALUES(？,？,？)";

$stmt=$pdo->prepare($sql);

$stmt->bindParam ( ‘username‘, $name );              //命名参数绑定

$stmt->bindParam(1, $name);             //？占位符绑定

$name = ‘soon‘;        //变量值

$stmt->execute (array(":username"=>"andy",":userpassword"=>"andy123",":userrole"=>"访客"));

$stmt->execute (array("username"=>"andy1","userpassword"=>"andy123","userrole"=>"访客"));

$option = array (
		PDO::ATTR_PERSISTENT => TRUE,
		PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
		PDO::ATTR_ORACLE_NULLS => true 
);

try {
	// 1.创建PDO对象
	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	// 2.准备SQL语句
	$sql = "INSERT INTO users(username,userpassword,userrole) VALUES(:username,:userpassword,:userrole)";
	// $sql="INSERT INTO users(username,userpassword,userrole) VALUES(?,?,?,?)";
	// 3.返回PDOStatement对象
	$stmt = $pdo->prepare ( $sql );
	// 4.绑定参数（使用命名参数作为占位符）
	// $stmt->bindParam ( ‘username‘, $name );
	// $stmt->bindParam ( ‘userpassword‘, $pwd );
	// $stmt->bindParam ( ‘userrole‘, $role );
	// 5.执行查询
	$stmt->execute ( array (
			"username" => "andy2",
			"userpassword" => "andy123",
			"userrole" => "访客" 
	) );
	echo ‘受影响行数：‘.$stmt->rowCount();
	echo ‘<br>新增访客编号为：‘.$pdo->lastInsertId();
	
} catch ( PDOException $e ) {
	echo ‘数据库操作失败：‘ . $e->getMessage ();
	exit ();
}

$option = array (
		PDO::ATTR_PERSISTENT => TRUE,
		PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
		PDO::ATTR_ORACLE_NULLS => true 
);

try {
	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	// 查询
	$sql = "SELECT * FROM users";
	// $stmt=$pdo->query($sql);
	$stmt = $pdo->prepare ( $sql );
	$stmt->execute ();
	
	echo "一共{$stmt->rowCount()}条记录<br>";
	echo "id---account---pwd---role<br>";
	// foreach ( $stmt as $row ) {
	// echo "{$row[‘id‘]},{$row[‘username‘]},{$row[‘userpassword‘]},{$row[‘userrole‘]}<br>";
	// }
	
	// while ($arr=$stmt->fetch(PDO::FETCH_NUM)){
	// echo $arr[0].‘---‘;
	// echo $arr[1].‘---‘;
	// echo $arr[2].‘---‘;
	// echo $arr[3].‘<br>‘;
	// }
	
	// while ( $arr = $stmt->fetch ( PDO::FETCH_ASSOC ) ) {
	// echo $arr [‘id‘] . ‘---‘;
	// echo $arr [‘username‘] . ‘---‘;
	// echo $arr [‘userpassword‘] . ‘---‘;
	// echo $arr [‘userrole‘] . ‘<br>‘;
	// }
	
	// while (list($id,$name,$pwd,$role)=$stmt->fetch(PDO::FETCH_NUM)){
	// echo "{$id}---{$name}---{$pwd}---{$role}<br>";
	// }
	
	$obj = $stmt->fetch ( PDO::FETCH_OBJ );
	var_dump($obj);
	
} catch ( PDOException $e ) {
	echo ‘数据库操作失败：‘ . $e->getMessage ();
	exit ();
}

$option = array (
		PDO::ATTR_PERSISTENT => TRUE,
		PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
		PDO::ATTR_ORACLE_NULLS => true
);

try {
	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	// 查询
	$sql = "SELECT * FROM users";
	$stmt = $pdo->prepare ( $sql );
	$stmt->execute ();
	$allRows=$stmt->fetchAll(PDO::FETCH_ASSOC);
	echo "一共{$stmt->rowCount()}条记录<br>";
	echo "id---account---pwd---role<br>";
	foreach ($allRows as $row){
echo "{$row[‘id‘]}---{$row[‘username‘]}---{$row[‘userpassword‘]}---{$row[‘userrole‘]}<br>";
	 }	
} catch ( PDOException $e ) {
	echo ‘数据库操作失败：‘ . $e->getMessage ();
	exit ();
}

$option = array (
		PDO::ATTR_PERSISTENT => TRUE,
		PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
		PDO::ATTR_ORACLE_NULLS => true
);

try {
	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	// 查询
	$sql = "SELECT * FROM users";
	$stmt = $pdo->prepare ( $sql );
	$stmt->setFetchMode(PDO::FETCH_BOUND);
	
	$stmt->execute ();	
	$stmt->bindColumn(1, $id);
	$stmt->bindColumn(2, $name);
	$stmt->bindColumn("userpassword", $pwd);
	$stmt->bindColumn("userrole", $role);
	while($stmt->fetch()){
		echo "{$id}---{$name}---{$pwd}---{$role}<br>";
	}

} catch ( PDOException $e ) {
	echo ‘数据库操作失败：‘ . $e->getMessage ();
	exit ();
}

	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	// 查询
	$sql = "SELECT * FROM users";
	$stmt = $pdo->prepare ( $sql );
	$stmt->execute ();
	echo ‘users表中总共有：‘.$stmt->columnCount().‘个字段‘;
	var_dump($stmt->getColumnMeta(0));//获取某个字段详细信息

<form action="action.php" method="post" enctype="multipart/form-data">
		<!-- 隐藏域，设置图片大小 -->
		<input type="hidden" name="MAX_FILE_SIZE" value="1000000"> 
		<p>选择文件：
		<input type="file" name="myfile"></p>		
		<p>文件描述：<input type="text" name="description"></p>
		<p><input type="submit" value="上传"></p>
	</form>

$allowtype = array (
		"gif",
		"png",
		"jpg",
		"jpeg" 
); // 设置充许上传的类型为gif, png, jpg,jpeg

$size = 1000000; // 设置充许大小为1M（1000000字节）以内的文件
$path = "./uploads"; // 设置上传后保存文件的路径，指定当前目录下的uploads目录

/* 判断文件是否可以成功上传到服务器，$_FILES[‘myfile‘][‘error‘]值为0表示上传成功 ，其它值则出错 */
if ($_FILES [‘myfile‘] [‘error‘] > 0) {
	echo ‘上传错误: ‘;
	switch ($_FILES [‘myfile‘] [‘error‘]) {
		case 1 :
			die ( ‘上传文件大小超出了PHP配置文件中的约定值：upload_max_filesize‘ );
		case 2 :
			die ( ‘上传文件大小超出了表单中的约定值：MAX_FILE_SIZE‘ );
		case 3 :
			die ( ‘文件只被部分上载‘ );
		case 4 :
			die ( ‘没有上传任何文件‘ );
		default :
			die ( ‘未知错误‘ );
	}
}

/* 判断上传的文件是否为充许的文件类型 */
// 文件名转数组，第一个元素文件名，第二个元素扩展名
$fileNameArray = explode ( ".", $_FILES [‘myfile‘] [‘name‘] );
// 输出文件名数组最后一个元素
$hz = strtolower ( array_pop ( $fileNameArray ) );
/* 通过判断文件的后缀方式，来决定文件是否是充许上传的文件类型 */
if (! in_array ( $hz, $allowtype )) {
	die ( "这个后缀是<b>" . $hz . "</b>, 不是充许的文件类型!" );
}

/*
 * 也可以通过获取上传文件的MIME类型中的主类型和子类型,来限制文件上传的类型
 * list($maintype,$subtype)=explode("/",$_FILES[‘myfile‘][‘type‘]);
 * if ($maintype=="text") { //通过主类型限制不能上传文本文件，例如.txt .html .php等文件
 * die(‘问题: 不能上传文本文件。‘); //如果用户上传文本文件则退出程序
 * }
 */

/* 判断上传的文件是否为充许尺寸范围内 */
if ($_FILES [‘myfile‘] ["size"] > $size) {
	die ( "超过了充许的<b>{$size}<b>字节大小!" );
}

/* 为了系统安全，也为了同名文件会被覆盖，上传后将文件名使用系统定义 */
$filename = date ( "YmdHis" ) . rand ( 100, 999 ) . "." . $hz;

/* 判断是否为上传文件 */
if (is_uploaded_file ( $_FILES [‘myfile‘] [‘tmp_name‘] )) {
	// 移动文件:从临时空间转移到目标位置
	// if (! move_uploaded_file ( $_FILES [‘myfile‘] ["tmp_name"], $path . ‘/‘ . $filename )) {
	// die ( ‘问题: 不能将文件移动到指定目录。‘ );
	// }
	//图片插入到数据库
	$option = array (
			PDO::ATTR_PERSISTENT => TRUE,
			PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
			PDO::ATTR_ORACLE_NULLS => true
	);	
	try {
		$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
		// 查询
		$sql = "INSERT INTO images(contenttype,imagedata,description) VALUES(:contenttype,:imagedata,:description)";
		$stmt = $pdo->prepare ( $sql );
		
		$fp=fopen( $_FILES [‘myfile‘] ["tmp_name"], ‘rb‘);//打开上传的文件
		
		$stmt->bindParam("contenttype", $_FILES [‘myfile‘] ["type"]);
		$stmt->bindParam("imagedata", $fp,PDO::PARAM_LOB);
		$stmt->bindParam("description", $_POST[‘description‘]);
		$stmt->execute ();	
	} catch ( PDOException $e ) {
		echo ‘数据库操作失败：‘ . $e->getMessage ();
		exit ();
	}
	
} else {
	die ( "问题: 上传文件{$_FILES[‘myfile‘][‘name‘]}不是一个合法文件!" );
}

/* 如果文件上传成功则输出 */
//echo "文件{$filename}上传成功,保存在目录{$path}中,大小为{$_FILES[‘myfile‘][‘size‘]}字节";
echo "图片保存数据库成功";

$option = array (
		PDO::ATTR_PERSISTENT => TRUE,
		PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
		PDO::ATTR_ORACLE_NULLS => true
);
try {
	$pdo = new PDO ( ‘mysql:dbname=football;host=localhost‘, ‘root‘, ‘rootkit‘, $option );
	$sql = "SELECT contenttype,imagedata,description FROM images WHERE id=:id";
	$stmt = $pdo->prepare ( $sql );
	$stmt->bindParam("id", $id);
	$id=2;
	$stmt->execute ();
	list($type,$lob,$des)=$stmt->fetch();
	header("Content-type:$type");
	echo $lob;	
} catch ( PDOException $e ) {
	echo ‘数据库操作失败：‘ . $e->getMessage ();
	exit ();
}

<?php
$pdo = new PDO ( "mysql:host=localhost;dbname=mybank", "root", "rootkit" );
$pdo->setAttribute ( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION ); // 设置异常处理模式

$pdo->setAttribute ( PDO::ATTR_AUTOCOMMIT, 0 ); // 关闭自动提交

try {
	$money = 8000; // 转账金额
	
	$pdo->beginTransaction (); // 开始事务
	
	$affected_rows = $pdo->exec ( "UPDATE bank1 SET amount=amount-{$money} WHERE id=1120553244123" ); // 张三账户转出
	if ($affected_rows > 0) {
		echo "张三账户成功转出{$money}元人民币<br>";
	} else {
		throw new PDOException ( ‘张三转出失败‘ ); // 失败抛出异常，不向下再执行，转到catch区块
	}
	
	$affected_rows = $pdo->exec ( "UPDATE bank2 SET amount=amount+{$money} WHERE id=2234753244567" ); // 李四账户转入
	if ($affected_rows > 0) {
		echo "李四账户成功转入{$money}元人民币<br>";
	} else {
		throw new PDOException ( ‘李四账户转入失败‘ ); // 失败抛出异常，不向下再执行，转到catch区块
	}
	echo "交易成功!";
	$pdo->commit (); // 如果执行到此处表示前面两个查询执行成功，整个事务执行成功
} catch ( PDOException $e ) {
	echo "交易失败:" . $e->getMessage ();
	$pdo->rollback (); // 如果执行到此处理表示事务中的语句出问题了， 整个事务全部撤消
}

$pdo->setAttribute ( PDO::ATTR_AUTOCOMMIT, 1 );          //重新开启自动提交