PHP用户名/密码安全性

I'm creating a login script for a website I'm developing. At the moment I have the usernames and passwords hard-coded into the script. i.e.

$usersAndPasses = array(
    'username1' => 'password1',
    'username2' => 'password2'
)

and so on

I was wondering if this is any less secure than placing them in a MySQL database.

Thanks

Not less secure ... unless of course there is file injection. However, it will also be a lot slower than querying the database if you have lots of members (which you would currently have to add in manually).

No. It is not less secure, unless someone steals your sources.