mysqli::real_connect(): (HY000/1049): Unknown database error in codeigniter

Question

I\'m new to Codeigniter PHP framework. When I\'m testing my application I get \'Unknown database db_name\' error. I have browsed through several sites but didn\'t found solu

Answer 1

I was getting same error when i installed new wampserver 3.2.0, it is an evil it installs MariaDB by default and port 3306 is assigned to it , you cannot even change it. I think codeigniter/php tries to connect to this port by default. I used following , it worked for me i.e. hostname => 'localhost:3308'

 $db['default'] = array(
        'dsn'   => '',
        'hostname' => 'localhost:3308',
        'username' => 'root',
        'password' => '',
        'database' => 'soft',
        'dbdriver' => 'mysqli',
        'dbprefix' => '',
        'pconnect' => FALSE,
        '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
    );

Answer 2

I was too getting this error. There are 2 fields in application/config/database.php file that should match up with your actual database:

'char_set' => 'utf8',
'dbcollat' => 'utf8_general_ci',

Make sure, the actual DB is of the same type & char_set as mentioned in the above file.

Answer 3

That's what i did to handle whether db exists or not :

First Change this in application/config/database.php

'db_debug' => (ENVIRONMENT !== 'production')

to

'db_debug' => FALSE; 

Then add these two in your controller

    $this->load->dbforge();
    $this->load->dbutil();

Then check it in your method

    if( $this->dbutil->database_exists($this->db->database))
    {
        echo 'Database Already Exists';
    }
    else
    {
        if($this->dbforge->create_database($this->db->database))
        {
            echo 'Database created successfully !';
        }else
        {
            print_r($this->db->error());
            /*
               Array ( 
                     [code] => 1007 
                     [message] => Can't create database 'my_db'; database exists 
                    )
           */
        }
    }