John Davidson

Message:

Just want to understand how to implement this before I go through with it. This regards the scope of PHP session variables. I understand the concept of a 'session', of course, but what I am less clear about is whether that 'session' is global to all users of a web application (i.e. in which case if more than one user was accessing the PHP portion of a page at the same time they might start swapping/switching out variables on each other, which would not be good).

Or does a 'unique' session begin for every user every time the script is called ? In which case the 'sessions' would be isolated?

If 'session' is merely global for all users, all the time, I think I am likely better off using cookies or other methods to pass data between scripts, though the session variables method does seem so clean and tidy, otherwise.

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My Answer:
In PHP, session variables are unique to each user's session. When a user accesses a PHP script, a unique session is started for that user and any session variables set during that session are only accessible to that user. This means that session variables are isolated and do not interfere with each other, even if multiple users are accessing the same PHP script at the same time.

Using session variables is a clean and tidy way to pass data between scripts for a specific user's session. It is a secure way to store user-specific information without exposing it to other users. Cookies can also be used to pass data between scripts, but they are not as secure as session variables because they are stored on the user's browser and can be manipulated by the user.

Overall, session variables are a good choice for storing user-specific data in PHP applications and should not cause any issues with variable scope or data interference between users.