Hola buenos días.
En mi caso, creé un array con las bases de datos.
Esto debe estar en tu carpeta_de_aplicaciones/config/database.php
Código PHP:
Ver original$db['db1']['hostname'] = "";
$db['db1']['port'] = "";
$db['db1']['username'] = "";
$db['db1']['password'] = "";
$db['db1']['database'] = "";
$db['db1']['dbdriver'] = "";
$db['db1']['dbprefix'] = "";
$db['db1']['pconnect'] = ;
$db['db1']['db_debug'] = ;
$db['db1']['cache_on'] = ;
$db['db1']['cachedir'] = "";
$db['db1']['char_set'] = "";
$db['db1']['dbcollat'] = "";
$db['db2']['hostname'] = "";
$db['db2']['port'] = "";
$db['db2']['username'] = "";
$db['db2']['password'] = "";
$db['db2']['database'] = "";
$db['db2']['dbdriver'] = "";
$db['db2']['dbprefix'] = "";
$db['db2']['pconnect'] = ;
$db['db2']['db_debug'] = ;
$db['db2']['cache_on'] = ;
$db['db2']['cachedir'] = "";
$db['db2']['char_set'] = "";
$db['db2']['dbcollat'] = "";
Y luego, cargas las bases de datos en los modelos:
$this->db1 = $this->load->database('db1', TRUE);
$this->db2 = $this->load->database('db2', TRUE);