1. The difference with mysql extension library:
(1) Higher security and stability
(2 provides two styles of object-oriented and process-oriented
2. Extension=php_mysqli.dll in php.ini is unsealed
3. Object-oriented: query list
1 <?php
2
3 //mysqli 操作数据（面向对象风格）
4
5 #1、创建Mysql对象
6
7 $mysqli=new MySQLi("127.0.0.1","root","daomul","test");
8 if(!$mysqli)
9 {
10 die("连接失败！".$mysqli->connect_error);
11 }
12
13 #2、操作数据库
14
15 $sql="select * from user1";
16 $res=$mysqli->query($sql);
17 #3、处理结果
18
19 while($row=$res->fetch_row())
20 {
21 foreach($row as $key=> $val)
22 {
23 echo "-- $val";
24 }
25 echo "<br/>";
26 }
27 #4、关闭资源
28 $res->free();//释放内存
29 $mysqli->close();//关闭连接
30
31 ?>
4. Object-oriented: implement after encapsulating the class
4.1 Sqliconnect.class.php
1 <?php
2
3 Class Sqliconnect
4 {
5 private $mysqli;
6 private static $host="127.0.0.1";
7 private static $root="root";
8 private static $password="daomul";
9 private static $db="test";
10
11 function __construct()
12 {
13 $this->mysqli=new MySQLi(self::$host,self::$root,self::$password,self::$db);
14 if(!$this->mysqli)
15 {
16 die("数据库连接失败！".$this->mysqli->connect_error);
17 }
18
19 $this->mysqli->query("set names utf8");
20 }
21
22 //查询操作
23 public function excute_dql($sql)
24 {
25 $res=$this->mysqli->query($sql) or die("数据查询失败".$this->mysqli->error);
26 return $res;
27
28 }
29
30 //增删改操作
31 public function excute_dml($sql)
32 {
33 $res=$this->mysqli->query($sql) or die("数据操作失败".$this->mysqli->error);
34 if(!$res)
35 {
36 echo "数据操作失败";
37 }
38 else
39 {
40 if($this->mysqli->affected_rows>0)
41 {
42 echo "操作成功！";
43 }
44 else
45 {
46 echo "0行数据受影响！";
47 }
48 }
49 }
50
51 }
52 ?>4.2 Call page startsqli.php
1 <?php
2
3 //mysqli 操作数据（面向对象风格）
4
5
6 require_once "Sqliconnect.class.php";
7
8 $Sqliconnect=new Sqliconnect();
9
10 //$sql="insert into user1(name,password,email,age) values('帝都',md5('gg'),'sd@sohu.com',23)";
11 //$sql="delete from user1 where id=11";
12 //$res=$Sqliconnect->excute_dml($sql);
13
14 $sql="select name from user1;";
15 $res=$Sqliconnect->excute_dql($sql);
16 while($row=$)
17
18 $res->free();
19 ?>
5. Execute multiple database statements at the same time multiQuery.php
1 <?php
2
3 //mysqli 操作数据（面向对象风格）
4
5 #1、创建Mysql对象
6
7 $mysqli=new MySQLi("127.0.0.1","root","daomul","test");
8 if(!$mysqli)
9 {
10 die("连接失败！".$mysqli->connect_error);
11 }
12
13 #2、操作数据库
14
15 $sqls="select * from user1;";
16 $sqls.="select * from user1";
17
18 #3、处理结果
19
20 if($res=$mysqli->multi_query($sqls))
21 {
22 echo "211";
23 do
24 {
25 //从mysqli连续取出第一个结果集
26 $result=$mysqli->store_result();
27
28 //显示mysqli result对象
29 while($row=$result->fetch_row())
30 {
31 foreach($row as $key=> $val)
32 {
33 echo "-- $val";
34 }
35 echo "<br/>";
36 }
37
38 $result->free();//及时释放当前结果集，并进入下一结果集
39
40 //判断是否有下一个结果集
41 if(!$mysqli->more_results())
42 {
43 break;
44 }
45 echo "<br/>************新的结果集**************";
46
47 }while($mysqli->next_result());
48 }
49
50 #4、关闭资源
51 $mysqli->close();//关闭连接
52
53
54 ?>
6. Transaction control
1 <?php
2
3 //mysqli 操作数据（面向对象风格）
4
5
6 // 数据库 ：create table account(id int primary key,balance float);
7
8 $mysqli=new MySQLi("127.0.0.1","root","daomul","test");
9 if(!$mysqli)
10 {
11 die("数据库连接失败！".$mysqli->connect_error);
12 }
13 //将提交设为false
14 $mysqli->autocommit(false);
15
16 $sql1="update account set balance=balance+1 where id=1;";//没错的语句
17 $sql2="update accounterror2 set balance=balance-1 where id=2";//有错的语句
18
19 $res1=$mysqli->query($sql1);
20 $res2=$mysqli->query($sql2);
21
22 if(!$res1||!$res2)
23 {
24 //回滚：其中一个不成功即回滚不提交
25 echo "有错，回滚，请重新提交！";
26 $mysqli->rollback();//die("操作失败！".$mysqli->error);
27 }
28 else
29 {
30 //所有均成功则提交
31 echo "所有提交成功！";
32 $mysqli->commit();
33 }
34
35 $mysqli->close();
36 /*
37 1、 start transaction; 开启事务
38 2、svaepoint a; 做保存点
39 3、执行操作1;
40 4、 svaepoint b;
41 5、执行操作2;
42 ...
43 6、rollback to a/b; 回滚或者是提交
44 7、commit
45
46 事务控制特点acid 原子性/一致性/隔离性/持久性
47 */
48 ?>7. Preprocessing technology
It mainly streamlines the connection and compilation process, and can also prevent SQL injection
7.1 Pre-compile and insert multiple data
1 <?php
2
3 //mysqli 预编译演示
4
5 #1、创建mysqli对象
6 $mysqli=new MySQLi("127.0.0.1","root","daomul","test");
7 if(!$mysqli)
8 {
9 die("数据库连接失败！".$mysqli->connect_error);
10 }
11
12 #2、创建预编译对象
13 $sql="insert into user1(name,password,email,age) values(?,?,?,?);";//暂时不赋值，用问号代替
14 $stmt=$mysqli->prepare($sql) or die($mysqli->error);
15
16 /********************************可重复执行时需要的代码start*********************************/
17 #3、绑定参数
18 $name='小明5';
19 $password='34f';
20 $email='ssd@qq.com';
21 $age='1';
22
23 #4、参数赋值（第一个参数指代参数的类型缩写，string-s,int-i,double-d,bool-b
24 $stmt->bind_param("sssi",$name,$password,$email,$age);
25
26 #5、执行代码（返回布尔类型）
27 $flag=$stmt->execute();
28
29 /********************************可重复执行时需要的代码 end************************************/
30
31 #6、结果以及释放
32
33 if(!$flag)
34 {
35 die("操作失败".$stmt->error);
36 }
37 else
38 {
39 echo "操作成功！";
40 }
41
42 $mysqli->close();
43
44
45 ?>7.2 Pre-compiled query for multiple data
1 <?php
2
3 //mysqli 预编译演示
4
5 #1、创建mysqli对象
6 $mysqli=new MySQLi("127.0.0.1","root","daomul","test");
7 if(!$mysqli)
8 {
9 die("数据库连接失败！".$mysqli->connect_error);
10 }
11
12 /********************************可重复执行时需要的代码 start*******************************/
13
14 #2、创建预编译对象
15 $sql="select id,name,email from user1 where id>?;";//id,name,email和后面的结果集bind_result()对应
16 $stmt=$mysqli->prepare($sql) or die($mysqli->error);
17
18 #3、绑定参数
19 $id=5;
20
21 #4、参数赋值（第一个参数指代参数的类型缩写，string-s,int-i,double-d,bool-b
22 $stmt->bind_param("i",$id);//绑定参数
23 $stmt->bind_result($id,$name,$email);//绑定结果集
24
25 #5、执行代码（返回布尔类型）
26 $stmt->execute();
27
28 #6、取出结果集显示
29 while($stmt->fetch())
30 {
31 echo "<br/>$id--$name--$email";
32 }
33
34 /********************************可重复执行时需要的代码 end*******************************/
35
36 #7、结果以及释放
37
38 //释放结果
39 $stmt->free_result();
40 //关闭预编译语句
41 $stmt->close();
42 //关闭数据库连接
43 $mysqli->close();
44
45
46 ?>
8. Other functions
(1 Get the number of rows and columns num_rows field_count
(2 Get a column of the result set: header, for example
$result=$mysqli->query();
$result->fetch_field();
(3 Get data
$row=$result->fetch_row(); //Get each row of data
Taking each data through Foreach ($ Row as $ Val) {}
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