Teach me how to program

Hello,

I already cek the manual and still do not understand how to fix this problem.

config/database.php

PHP Code:

$db['default'] = array(
    'dsn'    => '',
    'hostname' => 'localhost',
    'username' => 'gsaconst_admin',
    'password' => '*****************',
    'database' => 'gsaconst_database',
    'dbdriver' => 'mysqli_connect',
    'dbprefix' => 'pix_',
    'pconnect' => TRUE,
    'db_debug' => (ENVIRONMENT !== 'production'),
    'cache_on' => FALSE,
    'cachedir' => '',
    'char_set' => 'utf8',
    'dbcollat' => 'utf8_general_ci',
    'swap_pre' => '',
    'encrypt' => FALSE,
    'compress' => FALSE,
    'stricton' => FALSE,
    'failover' => array(),
    'save_queries' => TRUE
); 


http://www.codeigniter.com/user_guide/da..._DB_driver

class CI_DB_driver initialize()
 Returns:
TRUE on success, FALSE on failure
Return type:
bool

Initialize database settings, establish a connection to the database.


---------------------------------------------------------------

ERROR MESSAGE:


http://localhost/ci3/

An Error Was Encountered
Invalid DB driver

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