A little personal understanding of PDO and message queue

　What is a message queue? Baidu Encyclopedia says... A message queue... is a container that saves messages during their transmission.

　Looking at the various articles on the Internet, they all say that it is a data container that is used to cope with high concurrency and handle extremely large amounts of data. It can also be said that it uses various methods to first store data in a container... , and then slowly obtain data from this container to implement... asynchronous operation of the database... in order to reduce the pressure on the database.

　No matter what the message queue is, I personally think that it is a container for storing data. It is as simple and clear as that, haha, because my research on the message queue is relatively superficial.

However, here, I still want to show off a personal little experimental code. Haha, if the following things are too far away from the message queue, please don’t be surprised, because I have made it very clear above. Well, I still don't know much about this thing. I just show off my "literary talent" after work. Therefore, if I really misunderstand the message queue, I can only say, please correct my mistakes and let the author get lost. Know return.

　First give the content of the mysql database configuration file mysql.ini:

<span style="color: #800000; font-weight: bold">[</span><span style="color: #800000">database</span><span style="color: #800000; font-weight: bold">]</span><span style="color: #000000">
driver </span>=<span style="color: #000000"> mysql
host </span>= 127.0.0.1<span style="color: #000000">
port </span>= 3306<span style="color: #000000">
dbname </span>=<span style="color: #000000"> mysql
username </span>=<span style="color: #000000"> root
password </span>= 1234
<span style="color: #800000; font-weight: bold">[</span><span style="color: #800000">options</span><span style="color: #800000; font-weight: bold">]</span><span style="color: #000000">
PDO::MYSQL_ATTR_INIT_COMMAND </span>= set names utf8

Contents of the data table file queue.sql:

<span style="color: #008080">--</span><span style="color: #008080"> 消息队列测试</span><span style="color: #008080">
--</span><span style="color: #008080"> 商品表</span>
<span style="color: #0000ff">create</span> <span style="color: #0000ff">table</span><span style="color: #000000"> goods(
id </span><span style="color: #0000ff">int</span> unsigned <span style="color: #0000ff">primary</span> <span style="color: #0000ff">key</span><span style="color: #000000"> auto_increment,
goodsname </span><span style="color: #0000ff">varchar</span>(<span style="color: #800000; font-weight: bold">40</span>) <span style="color: #808080">not</span> <span style="color: #0000ff">null</span> comment <span style="color: #ff0000">'</span><span style="color: #ff0000">商品名</span><span style="color: #ff0000">'</span><span style="color: #000000">,
price </span><span style="color: #0000ff">decimal</span>(<span style="color: #800000; font-weight: bold">9</span>,<span style="color: #800000; font-weight: bold">2</span>) <span style="color: #808080">not</span> <span style="color: #0000ff">null</span> comment <span style="color: #ff0000">'</span><span style="color: #ff0000">价格</span><span style="color: #ff0000">'</span><span style="color: #000000">,
category_id </span><span style="color: #0000ff">tinyint</span> unsigned <span style="color: #808080">not</span> <span style="color: #0000ff">null</span> comment <span style="color: #ff0000">'</span><span style="color: #ff0000">商品类别id</span><span style="color: #ff0000">'</span><span style="color: #000000">,
sort </span><span style="color: #0000ff">tinyint</span> comment <span style="color: #ff0000">'</span><span style="color: #ff0000">商品排序</span><span style="color: #ff0000">'</span><span style="color: #000000">,
description </span><span style="color: #0000ff">varchar</span>(<span style="color: #800000; font-weight: bold">255</span>) comment <span style="color: #ff0000">'</span><span style="color: #ff0000">商品描述</span><span style="color: #ff0000">'</span><span style="color: #000000">,
remark </span><span style="color: #0000ff">varchar</span>(<span style="color: #800000; font-weight: bold">255</span>) comment <span style="color: #ff0000">'</span><span style="color: #ff0000">备注</span><span style="color: #ff0000">'</span><span style="color: #000000">
)engine InnoDB </span><span style="color: #0000ff">default</span> charset<span style="color: #808080">=</span><span style="color: #000000">utf8;
</span><span style="color: #0000ff">insert</span> <span style="color: #0000ff">into</span> goods <span style="color: #0000ff">values</span>(<span style="color: #0000ff">default</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">iPhone5s</span><span style="color: #ff0000">'</span>,<span style="color: #800000; font-weight: bold">5999</span>,<span style="color: #800000; font-weight: bold">1</span>,<span style="color: #800000; font-weight: bold">1</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">美国入口贵重电子产品</span><span style="color: #ff0000">'</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">请多多销售</span><span style="color: #ff0000">'</span>),(<span style="color: #0000ff">default</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">宏基手提电脑1</span><span style="color: #ff0000">'</span>,<span style="color: #800000; font-weight: bold">4888</span>,<span style="color: #800000; font-weight: bold">3</span>,<span style="color: #800000; font-weight: bold">1</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">价格划算好电脑</span><span style="color: #ff0000">'</span>,<span style="color: #0000ff">null</span>),(<span style="color: #0000ff">default</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">f-30绒衣</span><span style="color: #ff0000">'</span>,<span style="color: #800000; font-weight: bold">200</span>,<span style="color: #800000; font-weight: bold">2</span>,<span style="color: #800000; font-weight: bold">1</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">以纯白色厚皮羽绒服</span><span style="color: #ff0000">'</span>,<span style="color: #0000ff">null</span>),(<span style="color: #0000ff">default</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">n-100鞋子</span><span style="color: #ff0000">'</span>,<span style="color: #800000; font-weight: bold">300</span>,<span style="color: #800000; font-weight: bold">4</span>,<span style="color: #800000; font-weight: bold">1</span>,<span style="color: #ff0000">'</span><span style="color: #ff0000">Nick品牌</span><span style="color: #ff0000">'</span>,<span style="color: #0000ff">null</span>);

The following is the code for implementing PDO product storage using a simple message queue:

　Solemn reminder: Please read my annotations carefully. Please read my annotations carefully. Please read my annotations carefully. Important information needs to be said three times, haha!

<?<span style="color: #000000">php
namespace Home;
</span><span style="color: #008080">header</span>('content-type:text/html;charset=utf-8;'<span style="color: #000000">);
</span><span style="color: #008000">//</span><span style="color: #008000">引入PDO类</span>
<span style="color: #0000ff">use</span><span style="color: #000000"> \PDO;
</span><span style="color: #0000ff">use</span><span style="color: #000000"> \PDOStatement;
</span><span style="color: #0000ff">use</span><span style="color: #000000"> \PDOException;
</span><span style="color: #008000">/*</span><span style="color: #008000">简单消息队列</span><span style="color: #008000">*/</span>
<span style="color: #0000ff">class</span><span style="color: #000000"> Queue{
    </span><span style="color: #008000">//</span><span style="color: #008000">容器可以是私有，最好是公有</span>
    <span style="color: #0000ff">static</span> <span style="color: #0000ff">public</span> <span style="color: #800080">$container</span>=<span style="color: #0000ff">array</span><span style="color: #000000">();
    </span><span style="color: #008000">//</span><span style="color: #008000">把PDO对象存放到属性中是为了跨方法使用</span>
    <span style="color: #0000ff">static</span> <span style="color: #0000ff">private</span> <span style="color: #800080">$pdo</span><span style="color: #000000">;
    </span><span style="color: #008000">//</span><span style="color: #008000">构造函数实现初始化PDO连接数据库</span>
    <span style="color: #0000ff">public</span> <span style="color: #0000ff">function</span> __construct(<span style="color: #800080">$file</span> = './mysql.ini'){<span style="color: #008000">//</span><span style="color: #008000">mysql数据库的配置文件，./mysql.ini与这个类是同一个目录
        //parse_ini_file函数作用，解析并获取ini文件的参数，加true是二维数组</span>
        <span style="color: #800080">$dbini</span>        = <span style="color: #008080">parse_ini_file</span>(<span style="color: #800080">$file</span>,<span style="color: #0000ff">true</span><span style="color: #000000">);
        </span><span style="color: #800080">$driver</span>        = <span style="color: #800080">$dbini</span>['database']['driver'<span style="color: #000000">];
        </span><span style="color: #008000">//</span><span style="color: #008000">这里的数据库是mysql的总数据库</span>
        <span style="color: #800080">$dbname</span>        = <span style="color: #800080">$dbini</span>['database']['dbname'<span style="color: #000000">];
        </span><span style="color: #800080">$host</span>        = <span style="color: #800080">$dbini</span>['database']['host'<span style="color: #000000">];
        </span><span style="color: #800080">$port</span>        = <span style="color: #800080">$dbini</span>['database']['port'<span style="color: #000000">];
        </span><span style="color: #008000">//</span><span style="color: #008000">构造PDO连接数据库的第一个参数，这个参数这么设置纯属是PDO类的语法，不懂的可以百度一下，这里就不做详解了</span>
        <span style="color: #800080">$dsn</span> = <span style="color: #800080">$driver</span>.':'.'dbname='.<span style="color: #800080">$dbname</span>.';host='.<span style="color: #800080">$host</span>.';port='.<span style="color: #800080">$port</span><span style="color: #000000">;
        </span><span style="color: #008000">//</span><span style="color: #008000">其他连接数据库参数</span>
        <span style="color: #800080">$username</span>    = <span style="color: #800080">$dbini</span>['database']['username'<span style="color: #000000">];
        </span><span style="color: #800080">$password</span>    = <span style="color: #800080">$dbini</span>['database']['password'<span style="color: #000000">];
        </span><span style="color: #800080">$options</span>    = <span style="color: #800080">$dbini</span>['options'];<span style="color: #008000">//</span><span style="color: #008000">初始化设置PDO选项</span>
        <span style="color: #0000ff">try</span><span style="color: #000000">{
            self</span>::<span style="color: #800080">$pdo</span> = <span style="color: #0000ff">new</span> PDO(<span style="color: #800080">$dsn</span>,<span style="color: #800080">$username</span>,<span style="color: #800080">$password</span>,<span style="color: #800080">$options</span><span style="color: #000000">);
            </span><span style="color: #008000">//</span><span style="color: #008000">设置PDO属性。抛出错误报告</span>
            self::<span style="color: #800080">$pdo</span>->setAttribute(PDO::ATTR_ERRMODE,PDO::<span style="color: #000000">ERRMODE_EXCEPTION);
            </span><span style="color: #0000ff">try</span><span style="color: #000000">{
                </span><span style="color: #008000">//</span><span style="color: #008000">选择商品数据表所在的数据库</span>
                self::<span style="color: #800080">$pdo</span>-><span style="color: #008080">exec</span>('use queue'<span style="color: #000000">);
            }</span><span style="color: #0000ff">catch</span>(PDOException <span style="color: #800080">$e</span><span style="color: #000000">){
                </span><span style="color: #0000ff">echo</span> <span style="color: #800080">$e</span>-><span style="color: #000000">getMessage();
            }
        }</span><span style="color: #0000ff">catch</span>(PDOException <span style="color: #800080">$e</span><span style="color: #000000">){
            </span><span style="color: #0000ff">echo</span> <span style="color: #800080">$e</span>-><span style="color: #000000">getMessage();
        }
    }
    </span><span style="color: #008000">/*</span><span style="color: #008000">
    *入列
    *$data数组
    *成功返回1，失败返回false，或者null
    </span><span style="color: #008000">*/</span>
    <span style="color: #0000ff">public</span> <span style="color: #0000ff">function</span> _unshift(<span style="color: #800080">$data</span> =<span style="color: #0000ff">array</span><span style="color: #000000">()){
        </span><span style="color: #0000ff">if</span>(!<span style="color: #008080">is_array</span>(<span style="color: #800080">$data</span>) || <span style="color: #0000ff">empty</span>(<span style="color: #800080">$data</span>)){<span style="color: #0000ff">return</span> <span style="color: #0000ff">false</span><span style="color: #000000">;}
        </span><span style="color: #800080">$sql</span> = 'default'<span style="color: #000000">;
        </span><span style="color: #0000ff">foreach</span>(<span style="color: #800080">$data</span> <span style="color: #0000ff">as</span> <span style="color: #800080">$k</span>=><span style="color: #800080">$v</span><span style="color: #000000">){
            </span><span style="color: #800080">$sql</span> .= ',"'.<span style="color: #800080">$v</span>.'"'<span style="color: #000000">;
        }
        </span><span style="color: #008000">//</span><span style="color: #008000">把$data转为sql语句，添加到队列容器contain中</span>
        <span style="color: #800080">$sql</span> = 'insert into goods values('.<span style="color: #800080">$sql</span>.')'<span style="color: #000000">;
        </span><span style="color: #0000ff">return</span> @<span style="color: #008080">array_unshift</span>(self::<span style="color: #800080">$container</span>,<span style="color: #800080">$sql</span><span style="color: #000000">);
    }
    </span><span style="color: #008000">/*</span><span style="color: #008000">
    *出列
    *成功返回最后插入的数据id
    *失败返回失败信息
    </span><span style="color: #008000">*/</span>
    <span style="color: #0000ff">private</span> <span style="color: #0000ff">static</span> <span style="color: #0000ff">function</span><span style="color: #000000"> _pop(){
        </span><span style="color: #0000ff">try</span>{<span style="color: #008000">//</span><span style="color: #008000">获取尾部的sql语句，出列</span>
            <span style="color: #800080">$sql</span> = <span style="color: #008080">array_pop</span>(self::<span style="color: #800080">$container</span><span style="color: #000000">);
            self</span>::<span style="color: #800080">$pdo</span>-><span style="color: #008080">exec</span>(<span style="color: #800080">$sql</span><span style="color: #000000">);
            </span><span style="color: #008000">//</span><span style="color: #008000">把剩余的容器值赋给中间变量</span>
            <span style="color: #800080">$middle</span> = self::<span style="color: #800080">$container</span><span style="color: #000000">;
            </span><span style="color: #008000">//</span><span style="color: #008000">判断中间变量是否为空，不为空则继续获取容器尾部的数据，继续出列</span>
            <span style="color: #0000ff">while</span>(<span style="color: #800080">$middle</span><span style="color: #000000">){
                </span><span style="color: #800080">$sql</span> = <span style="color: #008080">array_pop</span>(<span style="color: #800080">$middle</span><span style="color: #000000">);
                self</span>::<span style="color: #800080">$pdo</span>-><span style="color: #008080">exec</span>(<span style="color: #800080">$sql</span><span style="color: #000000">);
                </span><span style="color: #008000">//</span><span style="color: #008000">把数据再转给容器，也就是转给while循环外面的$middle，这样才能实现循环，让容器里面的数据全部出列，插入到数据库中</span>
                self::<span style="color: #800080">$container</span> = <span style="color: #800080">$middle</span><span style="color: #000000">;
            }
            </span><span style="color: #008000">//</span><span style="color: #008000">返回的是，最后插入的id，失败是null</span>
            <span style="color: #0000ff">return</span> self::<span style="color: #800080">$pdo</span>-><span style="color: #000000">lastInsertId();

            }</span><span style="color: #0000ff">catch</span>(PDOException <span style="color: #800080">$e</span><span style="color: #000000">){
                </span><span style="color: #0000ff">return</span> <span style="color: #800080">$e</span>-><span style="color: #000000">getMessage();
            }
    }
    </span><span style="color: #008000">//</span><span style="color: #008000">析构函数，对象回收时调用，通过它实现自动让容器数据入库</span>
    <span style="color: #0000ff">public</span> <span style="color: #0000ff">function</span><span style="color: #000000"> __destruct(){
        </span><span style="color: #008000">//</span><span style="color: #008000">当对象被回收时，判断容器是否存在消息，假如存在，则调用_pop方法，把消息出列</span>
        <span style="color: #0000ff">if</span>(self::<span style="color: #800080">$container</span><span style="color: #000000">){
            self</span>::<span style="color: #000000">_pop();
        }
    }
}</span>

The following is the content of the file calling this class in the same level directory. Of course, you can also call the _unshift method under the queue class above to implement the message queue operation

<?<span style="color: #000000">php
</span><span style="color: #0000ff">include</span> './queue.php'<span style="color: #000000">;
</span><span style="color: #0000ff">use</span> Home\Queue;<span style="color: #008000">//</span><span style="color: #008000">引入命名空间的Queue类</span>
<span style="color: #800080">$ob</span> = <span style="color: #0000ff">new</span><span style="color: #000000"> Queue;
</span><span style="color: #008000">//</span><span style="color: #008000">消息入列</span>
<span style="color: #800080">$ob</span>->_unshift(<span style="color: #0000ff">array</span>('goodsname'=>'vivo手机8888','price'=>1120,'category_id'=>1,'sort'=>1,'description'=>'vivo品牌','remark'=>'好用'<span style="color: #000000">));
</span><span style="color: #800080">$ob</span>->_unshift(<span style="color: #0000ff">array</span>('goodsname'=>'小米手机888','price'=>1998,'category_id'=>1,'sort'=>1,'description'=>'小米品牌手机','remark'=>'国产好货'<span style="color: #000000">));
</span><span style="color: #008000">//</span><span style="color: #008000">之所以打印出来，完成是为了看看效果，至于，有没有实现商品入库，你得去看看你的数据库了，呵呵</span>
<span style="color: #008080">var_dump</span>(Queue::<span style="color: #800080">$container</span>);