我看见很多都将session写入数据库。如果将session写入数据库,是不是相当于自己实现了数据库的session?原来自带的就失效了?
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我看见很多都将session写入数据库。如果将session写入数据库,是不是相当于自己实现了数据库的session?原来自带的就失效了?
这个问题我觉得首先要先明确到底什么是session,个人觉得session是一种实现,跟cookie性质不太一样。
举例登录 http://segmentfault.com/
-
登录成功的时候服务器会生成一个类似
diM4og.6c3c602eff435b68a0e2aeca90254482.a
的随机字符串,并将这个字符串与我的id(1030000000093602)关联起来存储在 服务器端 ,这样服务器端就知道diM4og.6c3c602eff435b68a0e2aeca90254482.a
这个字符串属于哪个用户了。当然存储方式就随意选择了,以文件形式存储、数据库、redis、memcached
同时会在用户登录成功后将
diM4og.6c3c602eff435b68a0e2aeca90254482.a
这个字符串以cookie的形式发送给客户端浏览器。 以 sf 为例,这个字符串存储在一个名为sfsess
的cookie中。这样,登录后的每次访问,服务器端都会从客户端发来的cookie中读取中这个字符串,在服务器端查询是否有这个字符串的登录记录,有的话根据与之关联的
id
显示用户已登录。
这就是 session 的实现原理,python,java做的网站也一样,都是这个道理
下面说下PHP自带的 $_SESSION
,在我们用这句代码的时候,其实php同样做了上面的事情,只不过它是自动的,不用考虑具体实现。php服务器端存储session字符串是以文件形式存储的,客户端的cookie名是 PHPSESSION
,session过期什么的都由php自动管理了,当然cookie名称和过期时间等都可以通过配置php更改。
这就是php的优点,其实语言需要单独实现的session模块它一句代码搞定了。当然这也是它的缺点,使我们难以理解session的具体概念以及实现原理。
我看见很多都将session写入数据库。如果将session写入数据库,是不是相当于自己实现了数据库的session?原来自带的就失效了?
所以并不存在自带的失不失交的问题,只是以更屌的方式自己实现了session的验证而已,抛开了php的傻瓜代码。
另:sf 应该用的 redis 存储,Typecho用的数据库存储,楼主可以参考一下。
只是更改了session存放的地方,session还存在,只是从数据库里调用。

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Tracking user session activities in PHP is implemented through session management. 1) Use session_start() to start the session. 2) Store and access data through the $_SESSION array. 3) Call session_destroy() to end the session. Session tracking is used for user behavior analysis, security monitoring, and performance optimization.

Using databases to store PHP session data can improve performance and scalability. 1) Configure MySQL to store session data: Set up the session processor in php.ini or PHP code. 2) Implement custom session processor: define open, close, read, write and other functions to interact with the database. 3) Optimization and best practices: Use indexing, caching, data compression and distributed storage to improve performance.

PHPsessionstrackuserdataacrossmultiplepagerequestsusingauniqueIDstoredinacookie.Here'showtomanagethemeffectively:1)Startasessionwithsession_start()andstoredatain$_SESSION.2)RegeneratethesessionIDafterloginwithsession_regenerate_id(true)topreventsessi

In PHP, iterating through session data can be achieved through the following steps: 1. Start the session using session_start(). 2. Iterate through foreach loop through all key-value pairs in the $_SESSION array. 3. When processing complex data structures, use is_array() or is_object() functions and use print_r() to output detailed information. 4. When optimizing traversal, paging can be used to avoid processing large amounts of data at one time. This will help you manage and use PHP session data more efficiently in your actual project.

The session realizes user authentication through the server-side state management mechanism. 1) Session creation and generation of unique IDs, 2) IDs are passed through cookies, 3) Server stores and accesses session data through IDs, 4) User authentication and status management are realized, improving application security and user experience.


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