【Mysqli面向对象方式操作数据库】
添加、修改、删除数据
$mysqli = new mysqli('localhost','root','','test');
$mysqli->query('set names utf8');
//添加数据
$result = $mysqli->query("INSERT INTO users(name,money) VALUE ('张三',10)");
$result = $mysqli->query("INSERT INTO users(name,money) VALUE ('李四',200)"); //修改数据
$result = $mysqli->query("UPDATE users SET money=money+10 WHERE id = 3"); //删除数据
$result = $mysqli->query("DELETE FROM users WHERE id=3"); var_dump($result);
查询数据
header("content-type:text/html;charset=utf-8");
$mysqli = new mysqli('localhost','root','','test');
$mysqli->query('set names utf8'); $result = $mysqli->query("SELECT * FROM users");
$data = $result->fetch_all(MYSQLI_ASSOC);
var_dump($data);
事务控制
header('content-type:text/html;charset=utf-8');
$mysqli = new mysqli('localhost','root','','test');
$mysqli->query('set names utf8');
$mysqli->autocommit(false); //开启事务
$sql1 = "UPDATE users SET money=money-10 where id=1";
$sql2 = "UPDATE users SET money=money+10 where id=20";
$mysqli->query($sql1);
$r1 = $mysqli->affected_rows;
$mysqli->query($sql2);
$r2 = $mysqli->affected_rows;
if($r1>0 && $r2>0){
$mysqli->commit(); //事务提交
echo '操作成功';
}else{
$mysqli->rollback(); //事务回滚
echo '操作失败';
}
预处理-增删改操作
header('content-type:text/html;charset=utf-8');
$mysqli = new mysqli('localhost','root','','test');
$mysqli->query('set names utf8');
$sql = "INSERT INTO users(name,money) VALUE(?,?)";
$stmt = $mysqli->prepare($sql); $name = "王小小";
$money = 500;
$stmt->bind_param('si',$name,$money);
$result = $stmt->execute();
var_dump($result); $name = "王大大";
$money = 600;
$stmt->bind_param('si',$name,$money);
$result = $stmt->execute();
var_dump($result);
预处理-查询操作
header('content-type:text/html;charset=utf-8');
$mysqli = new mysqli('localhost','root','','test');
$mysqli->query('set names utf8');
$sql = "SELECT * FROM users WHERE id>?";
$stmt = $mysqli->prepare($sql);
$id=1;
$stmt->bind_param('i',$id);
$stmt->bind_result($id,$name,$money);
$stmt->execute(); while($stmt->fetch()){
$data[] = [
'id'=>$id,
'name'=>$name,
'money'=>$money
];
}
var_dump($data);
【PDO方式操作数据库】
PDO查询数据
header('content-type:text/html;charset=utf-8');
$dsn = "mysql:host=localhost;dbname=test";
$pdo = new PDO($dsn,'root','');
$pdo->exec('set names utf8');
$sql = "SELECT * FROM users";
$stmt = $pdo->query($sql);
//$data = $stmt->fetch(PDO::FETCH_ASSOC);
$data = $stmt->fetchAll(PDO::FETCH_ASSOC);
var_dump($data);
PDO增删改数据
header('content-type:text/html;charset=utf-8');
$dsn = "mysql:host=localhost;dbname=test";
$pdo = new PDO($dsn,'root','');
$pdo->exec('set names utf8');
$sql = "UPDATE users SET money=500 WHERE id=1";
$result = $pdo->exec($sql);
var_dump($result);
PDO事务控制
header('content-type:text/html;charset=utf-8');
$dsn = "mysql:host=localhost;dbname=test";
$pdo = new PDO($dsn,'root','');
$pdo->exec('set names utf8');
$pdo->beginTransaction(); //开启事务
$sql1 = "UPDATE users SET money=money-100 WHERE id=1";
$r1 = $pdo->exec($sql1); $sql2 = "UPDATE1 users SET money=money+100 WHERE id=2";
$r2 = $pdo->exec($sql2); if($r1>0 && $r2>0){
$pdo->commit(); //事务提交
echo "操作成功";
}else{
$pdo->rollBack(); //事务回滚
echo "操作失败";
}
$pdo->setAttribute(PDO::ATTR_AUTOCOMMIT,1);
//var_dump($result);
PDO预处理
header('content-type:text/html;charset=utf-8');
$dsn = "mysql:host=localhost;dbname=test";
$pdo = new PDO($dsn,'root','');
$pdo->exec('set names utf8'); //$sql = "SELECT * FROM users WHERE id>:id";
$sql = "UPDATE users SET money=1000 WHERE id=:id";
$stmt = $pdo->prepare($sql); $id = 4;
$stmt->bindParam(":id",$id); //$stmt->bindValue(1,2); $result = $stmt->execute();
var_dump($result); //$data = $stmt->fetchAll(PDO::FETCH_ASSOC);
//var_dump($data);
常见的SQL注入方式及防范措施
header('content-type:text/html;charset=utf-8');
$dsn = "mysql:host=localhost;dbname=test";
$pdo = new PDO($dsn,'root','');
$pdo->exec('set names utf8');
$id = isset($_GET['id'])?$_GET['id']:1;
$sql = "SELECT * FROM users WHERE id=".$id;
$stmt = $pdo->query($sql);
$data = $stmt->fetchAll(PDO::FETCH_ASSOC);
var_dump($data); //SELECT * FROM users WHERE id=1
//SELECT * FROM users WHERE id=1 or 1=1 SELECT * FROM users
//SELECT * FROM users WHERE id=1;drop table test;--
或
header('content-type:text/html;charset=utf-8');
$dsn = "mysql:host=localhost;dbname=test";
$pdo = new PDO($dsn,'root','');
$pdo->exec('set names utf8'); $sql = "SELECT * FROM users WHERE id=:id";
$stmt = $pdo->prepare($sql);
$id = isset($_GET['id'])?$_GET['id']:1;
$stmt->bindParam(":id",$id); $result = $stmt->execute();
$data = $stmt->fetchAll(PDO::FETCH_ASSOC);
var_dump($data);