my $dbh = DBI->connect(
    "DBI:mysql:$self->{DB_NAME}:$self->{DB_HOSTNAME}:$self->{DB_PORT}",
    $self->{DB_USERNAME},
    $self->{DB_PASSWORD},
    {
        PrintError  => 0,
        RaiseError  => 1,
    }
) or croak DBI->errstr;