I think the underlying question you're asking is "can I keep my database login info in some external resource on the server rather than hard-coding it into the script?" There's a question that goes along with that one, which is "how are you going to keep that resource from being visible to the world?" The answers don't have all that much to do with Perl, but here's a fairly common way of doing it (assuming that you're using Apache or something else that honors .htaccess files):

1) Ensure that you have a .htaccess file in the appropriate directory, and that it's set up to deny external access to the file that you want to use - e.g., if you wanted to use a file called .htinfo, it would look like this:

<Files .htinfo>
order allow,deny
deny from all
</Files>
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2) Create .htinfo and enter the necessary information. E.g.:

%info = (
    db      =>  'my_database_name',
    user    =>  'user_name',
    pass    =>  'password'
);
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3) Read it into your application.

our %info;
do ".htinfo" or die "Problem reading '.htinfo'!\n";
my $dbh = DBI->connect( "DBI:mysql:$info{db}", $info{user}, $info{pass
+} );
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