Site online with db offline

I deactivate the db_debug, I turn off the database and I received this error:

Code:

A PHP Error was encountered

Severity: Warning

Message: mysqli::real_connect(): (HY000/2002): No such file or directory

Filename: mysqli/mysqli_driver.php

Line Number: 135

Backtrace:

File: /Applications/XAMPP/xamppfiles/htdocs/arcor/application/models/Ranks.php
Line: 36
Function: database

File: /Applications/XAMPP/xamppfiles/htdocs/arcor/application/core/MY_Controller.php
Line: 47
Function: players

File: /Applications/XAMPP/xamppfiles/htdocs/arcor/application/core/MY_Controller.php
Line: 11
Function: players_rapid

File: /Applications/XAMPP/xamppfiles/htdocs/arcor/index.php
Line: 292
Function: require_once

Code:

Fatal error: Call to a member function real_escape_string() on boolean in /Applications/XAMPP/xamppfiles/htdocs/arcor/system/database/drivers/mysqli/mysqli_driver.php on line 331
A PHP Error was encountered

Severity: Error

Message: Call to a member function real_escape_string() on boolean

Filename: mysqli/mysqli_driver.php

Line Number: 331

Backtrace:

The connections I make them by the manual: $DB1 = $this->load->database('group_one', TRUE);
$DB2 = $this->load->database('group_two', TRUE);