如何在单个会话期间更改数据库

Question

I need to achieve the functionality where users can change databases on the fly. Once changed, the current database will be used across all php files making db calls.

So, I am trying to find the best solution to switch and remember the current database params during a single session. This is what I am doing at the moment:

1) php connection files conn1.php, conn2.php, conn3.php etc. containing different database connection parameters (name, password etc - $hostname, $username and so on).

2) when a user changes the database, the current database code is saved as a session variable $currDB.

3) All files that contains db calls, have a db connection switch on the top:

switch ($currDB){
     case 1:
          require_once('conn1.php');
          break;
     case 2:
          require_once('conn2.php');
          break;
    ........
}
$mysqli = new mysqli($hostname,$username,$password,$database);

Is there a more elegant way of achieving the same functionality of switching databases based on the user selection? I am not sure if maintaining session vars across multiple files would be the best option.

Any better ideas?

Thanks

Answer 1

I recommend, you do something like

• get $currentDB from the session or user input
• sanitize it to an int, either via (int) or e.g. is_numeric() followed by abs(round(..)) on very old PHP versions

now just @require_once("conn$currentDB.php"); and check for errors.

Last step is to put this into conn.php and include it from all consumers.