gistfile1.pl

sub frobnicate {
    #...
    my $dbh = MyApp->dbh;
    #...
}

# or

sub frobnicate {
    #...
    my $some_variable = MyApp::OurConstant;
    #...
}

# or

sub frobnicate {
    #...
    my $sql  = MyApp::Common::DBConnect(config => 'master');
    #...
}