Codeigniter - Using Multiple Databases

Question

database.php:

$db[\'default\'][\'hostname\'] = \"192.168.2.104\";
$db[\'default\'][\'username\'] = \"webuser\";
$db[\'default\'][\'password\         


        

Answer 1

You don’t need to create separate database configurations if you only need to use a different database on the same connection. You can switch to a different database when you need to, like this:

$this->db->db_select($database2_name);

CodeIgbiter User Guide

Answer 2

You may try modifying function CI_Session() in session.php file.

Replace

$this->CI->load->database();

with this

$this->CI->db1 = $this->CI->load->database('default', TRUE);
$this->CI->db2 = $this->CI->load->database('db2', TRUE);

In this way, you need not load 2 dbs in all the model files but shall use them directly using objects.

$this->db1 would be accessing default group db and $this->db2 would be accessing db2 group db. (both db groups should have been defined in database.php)

---

Sundar

Answer 3

currently, codeigniter cannot connect to multiple database in persisten connection. so, you should turn of the persisten of your connections. you may can do this..

$db['default']['pconnect'] = FALSE;

$db['stats']['pconnect'] = FALSE;

Answer 4

I fix the problem changing the DB_driver.php on the framework.

In this function I add $this->db_select(); and you never lose your connection again when working with 2 databases.

function simple_query($sql)
{
    if ( ! $this->conn_id)
    {
        $this->initialize();
    }

    $this->db_select();

    return $this->_execute($sql);
}

Answer 5

Instead of applying the hack as mentioned by Camacho you can also set the 'pconnect'-flag in the database.php file to FALSE for all connections.

Answer 6

There is a bug in codeigniter. Inserting one line into a class will fix the whole thing. Here is the original source: http://koorb.wordpress.com/2007/11/16/codeigniter-connect-to-multiple-databases/

** This fix does not apply to PostgreSQL

Here is a copy just in case that site goes down.

The line number has changed. Here is the bug fix from codeigniter:

start bugfix

Description

all of the database calls go to the same database (last one initialized)

To fix the problem change the simple_query function in /system/database/DB_driver.php:

function simple_query($sql)
{
    if ( ! $this->conn_id)
    {
        $this->initialize();
    }
   
    $this->db_select(); //<-----------------  Added this line
    return $this->_execute($sql);
}

This completely fixes the problem, so you can do stuff like this in a model

$this->legacy_db = $this->load->database('legacy', true);