codeigniter connect two database

问题

I use codeigniter 2.1.4. I record my session to my database1, and I query database2 data. But session will not found database2 table. I don't want to record session to database2.

The error message.

A Database Error Occurred

Error Number: 1146

Table 'database2.sessions' doesn't exist

SELECT * FROM (`sessions`) WHERE `session_id` = 'fd384ac44b1fe1c073cfc23185esdfda' AND `user_agent` = 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.76 Safari/537.36'

Filename: libraries/Session.php

Line Number: 213

My database.php.

$active_group = 'default';
$active_record = TRUE;

$db['default']['hostname'] = 'localhost';
$db['default']['username'] = 'root';
$db['default']['password'] = 'password';
$db['default']['database'] = 'database1';
$db['default']['dbdriver'] = 'mysql';
$db['default']['dbprefix'] = '';
$db['default']['pconnect'] = TRUE;
$db['default']['db_debug'] = TRUE;
$db['default']['cache_on'] = FALSE;
$db['default']['cachedir'] = '';
$db['default']['char_set'] = 'utf8';
$db['default']['dbcollat'] = 'utf8_general_ci';
$db['default']['swap_pre'] = '';
$db['default']['autoinit'] = TRUE;
$db['default']['stricton'] = FALSE;

$db['database2']['hostname'] = 'localhost';
$db['database2']['username'] = 'root';
$db['database2']['password'] = 'password';
$db['database2']['database'] = 'database2';
$db['database2']['dbdriver'] = 'mysql';
$db['database2']['dbprefix'] = '';
$db['database2']['pconnect'] = TRUE;
$db['database2']['db_debug'] = TRUE;
$db['database2']['cache_on'] = FALSE;
$db['database2']['cachedir'] = '';
$db['database2']['char_set'] = 'utf8';
$db['database2']['dbcollat'] = 'utf8_general_ci';
$db['database2']['swap_pre'] = '';
$db['database2']['autoinit'] = FALSE;
$db['database2']['stricton'] = FALSE;

My config.php

$config['sess_cookie_name']     = 'ci_session';
$config['sess_expiration']      = 7200;
$config['sess_expire_on_close'] = FALSE;
$config['sess_encrypt_cookie']  = TRUE;
$config['sess_use_database']    = TRUE;
$config['sess_table_name']      = 'sessions';
$config['sess_match_ip']        = FALSE;
$config['sess_match_useragent'] = TRUE;
$config['sess_time_to_update']  = 300;

That is my query database2 code.

  function ip_get($ip) {
    $db_rentcar = $this->load->database('rent_car', TRUE);
    $db_rentcar->from('ip');
    $db_rentcar->where('ip_ip', $ip);
    if($db_rentcar->count_all_results() == 1) {
      $query = $db_rentcar->get_where('ip', array('ip_ip' => $ip));
      return $query->row_array();
    } else {
      return array('ip_name' => 'user1', 'ip_type' => 1);
    }
  }

I have try to add this code to Session.php.

$this->CI->load->database('database1', TRUE);

The error become. How to solve the problem? Thanks.

An Error Was Encountered

You have specified an invalid database connection group.

回答1:

Your active db is the last one that you define last in database.php To connect next one connect it manually or put it in My_Controller if you always need to connect.

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

For your reference find more detail here

回答2:

Connecting to Multiple Databases

If you need to connect to more than one database simultaneously you can do so as follows:

$DB1 = $this->load->database('group_one', TRUE);
$DB2 = $this->load->database('group_two', TRUE);

Note: Change the words "group_one" and "group_two" to the specific group names you are connecting to (or you can pass the connection values as indicated above).

By setting the second parameter to TRUE (boolean) the function will return the database object.

When you connect this way, you will use your object name to issue commands rather than the syntax used throughout this guide. In other words, rather than issuing commands with:

$this->db->query();
$this->db->result();
etc...

You will instead use:

$DB1->query();
$DB1->result();
etc...

view official documentation https://www.codeigniter.com/userguide3/database/connecting.html#connecting-to-multiple-databases

回答3:

I found the answer.

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

    $this->db_select();  // Add this code

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

Reference here

来源：https://stackoverflow.com/questions/19063324/codeigniter-connect-two-database