Multiple databases across all models without breaking reusability

[eluser]pickupman[/eluser]
CI will on load one instance of an object. You can code loading a class a 100 times, and CI should load it just once. You may want to look at extending the models class (CI_Model). By extending the model class, you can add in the constructor to load both DB's. You would just need to remember to use MY_Model in any future project you would like to reuse your models in. There are some popular [url="https://bitbucket.org/jamierumbelow/codeigniter-base-model"]MY_Model[/url] files out there that build in some basic CRUD stuff.

Code:

//application/core/MY_Model.php
class MY_Model extends CI_Model{

  public function __construct(){
     parent::__construct();
     //Load DB1 stuff here

     //Load DB2 stuff here
  }
}

//In the rest of your models
class User_model extends MY_Model{
  
  public function __construct(){
    parent::__construct(); //Loads contruct from MY_Model which is loading your DB stuff
  }

  //rest of code here
}