The site does not start problems with the database, what's the problem?

Question

CodeIgniter

Hello, I uploaded the finished script to the host, bought a domain, did everything right in the database, but when I started the site, there was
a database error.
The specified database could not be selected: database name

Filename: core/MY_Controller.php

Line Number: 4
what could be the reason?

Answer 1

I suspect there is codeigniter
There is a suspicion, you need to get into the config
/application/config/database.php
And change the driver there to mysqli
Well, in the same place, change the login password database settings from the host