Follow their documentations. Quick links:
- https://github.com/yiisoft/db/blob/master/docs/guide/en/connection/mysql.md (I did not need the snippet with "new DsnSocket()")
- https://github.com/yiisoft/db-migration/blob/master/docs/guide/en/README.md (I recommend "Yii Console" installation)

> The documentations want you to create 2 files:
> - config/common/di/db-mysql.php > - config/common/db.php ...> - But you actually need only one. I recommend **db-mysql.php** > Note: If you want to create a file using commandline, you can use command "touch". For example "touch config/common/di/db-mysql.php"  
n


> Note: In the documentation the PHP snippets do not contain tag and declaration. Prepend it:

```php
<?php