PHP：PDO类完成增、删、改和查操作

1.PDO类完成增、删、改和查操作

pdo查询数据

<?php 

$pdo=new PDO('mysql:host=localhost;dbname=yzmedu','root','123');
$pdo->exec('set names utf8');

$sql="select * from user";
$smt=$pdo->query($sql);
$rows=$smt->fetchAll(PDO::FETCH_ASSOC);

echo '<pre>';
print_r($rows);
echo '</pre>';
 ?>

           

数据插入

<?php 

$pdo=new PDO('mysql:host=localhost;dbname=yzmedu','root','123');
$pdo->exec('set names utf8');

$sql="insert into user(username,password) values('user9','999')";

if($pdo->query($sql)){
	echo '数据添加成功!';
}
 ?>

           

PDO修改

<?php 

$pdo=new PDO('mysql:host=localhost;dbname=yzmedu','root','123');
$pdo->exec('set names utf8');

$sql="update user set password='999'";

if($num=$pdo->exec($sql)){
	echo "成功修改了{$num}行!";
}else{
	echo '修改失败!';
}
 ?>

           

PDO删除数据

<?php 

$pdo=new PDO('mysql:host=localhost;dbname=yzmedu','root','123');
$pdo->exec('set names utf8');

$sql="delete from user where id>3";

if($num=$pdo->exec($sql)){
	echo "成功删除{$num}行!";
}else{
	echo '删除失败!';
}
 ?>