$dbh = DBI->connect( $connect_string, \%attr );
    
    isa_ok $dbh, 'DBI::db';

    if ( defined($dbh) ) {
        write_log( "INFO    ", "Database connection OK" );
    }
    else {
        write_log( "FAIL    ", "Fail: $connect_string" );
        write_log( "FAIL    ", "Error connecting to database: Error $DBI::err - $DBI::errstr" );
        die "Error connecting to database: Error $DBI::err - $DBI::errstr";
    }