1、在PHP中 使用mysqli擴展庫對mysql 的dql操作

復制代碼 代碼如下:

<?php
    header("Content-type: text/html;charset=utf-8");
    //mysqli操作mysql數據庫(面向對象方式)
    //1、創建MySQLi對象
    $mysqli =new MySQLi("localhost","root","root","test");
    if($mysqli->connect_error){
        die("連接失敗".$mysqli->connect_error);
    }
    //2、操作數據庫（發送sql）
    $sql="select *from user1";
    //3、處理結果
    $res =$mysqli->query($sql);
    //var_dump($res);
    //fetch_assoc \fetch_array \fetch_object
    while($row=$res->fetch_row()){
        var_dump($row);
/*        foreach($row as $val){
            echo '--'.$val;
        }
        echo '<br/>';*/
    }
    //4、關閉資源
    $res->free();
    $mysqli->close();
?>

下面是面向過程的

復制代碼 代碼如下:

<?php
    header("Content-type: text/html;charset=utf-8");

    $mysqli=mysqli_connect("localhost","root","root","test");
    if(!$mysqli){
        die("連接失敗".mysqli_connect_error());
    }
    $sql="select *from user1";
    $res=mysqli_query($mysqli,$sql);
    //var_dump($res);
    while($row=mysqli_fetch_row($res)){

        foreach ($row as $val){

            echo '-'.$val;
        }
        echo '<br/>';
    }
    //釋放內存
    mysqli_free_result($res);
    mysqli_close($mysqli);
?>

2、在PHP中 使用mysqli擴展庫對mysql 的dml操作

復制代碼 代碼如下:

<?php

    //使用mysqli 擴展庫對mysql的crud 操作
    header("Content-type: text/html;charset=utf-8");
    $mysqli = new MySQLi("localhost","root","root","test");
    if($mysqli->connect_error){
        die("連接失敗".$mysql->connect_error);
    }
    //增加一條記錄
    //$sql="insert into user1 (name,password,email,age) values ('lucy',md5('lucy'),'lucy@163.com',17)";
    //刪除一條記錄
    //$sql="delete from user1 where id =80";
    //更新一條記錄
    $sql="update user1 set age=20 where id=7";
    $res=$mysqli->query($sql);
    if(!$res){
        echo "操作失敗".$mysqli->error;
    }else{
        if($mysqli->affected_rows>0){
            echo "成功";
        }else{
            echo "沒有行受影響";   
        }
    }
    //關閉資源
    $mysqli->close();
?>

3、進行封裝

復制代碼 代碼如下:

<?
    class SqlHelper{

        private $mysqli;
        //這里先寫死，以后寫死的東西用一個文件來配置
        private static $host="localhost";
        private static $user="root";
        private static $pwd="root";
        private static $db="test";
        public function __construct(){

            $this->mysqli=new MySQLi(self::$host,self::$user,self::$pwd,self::$db);
            if($this->mysqli->connect_error){
                die("連接失敗".$this->mysqli->connect_error);
            }
            //設置字符集
            $this->mysqli->query("set names utf8");
        }
        //dql operate
        function execute_dql($sql){
            $res =$this->mysqli->query($sql) or die($this->mysqli->error);
            return $res;       
        }
        //dml operate
        function execute_dml($sql){
            $res =$this->mysqli->query($sql) or die($this->mysqli->error);

            if(!$res){
                return 0;//失敗
            }else{
                if($this->mysqli->affected_rows>0){
                    return 1;//成功
                }else{
                    return 2;//沒有行到影響
                }
            }
        }
    }
?>