open   -> open    = add
open   -> hold    = add
open   -> closed  = add
hold   -> open    = sub
hold   -> hold    = ignore
hold   -> closed  = sub
closed -> open    = ignore
closed -> hold    = ignore
closed -> closed  = ignore

##</code><code>##

open -> anything    = add
closed -> anything  = ignore
hold -> hold        = ignore
hold -> open/closed = sub

##</code><code>##

my $dbh = DBI->connect("dbi:Sybase:server=CASTOR",$USER, $PASS);
my $select = "select entrydate,status, id from database 
              order by id, entrydate";
my $sth=$dbh->prepare($select);
$sth->execute;

my ($entrydate, $statusid, $objectid) = $sth->fetchrow;
my ($nentrydate, $nstatusid, $nobjectid);

while ( my $row = $sth->fetchrow_arrayref) {
    ($nentrydate, $nstatusid, $nobjectid) = 
       ($entrydate, $statusid, $objectid);
    ($entrydate, $statusid, $objectid) = @$row;

    # "closed" status can be ignored
    next if ($nstatusid eq "closed");
    if ($nobjectid eq $objectid) { 
	# object ids can be compared
	if ($nstatusid eq "start") {
	   $CUSTHOLD += parse_date($entrydate) - 
	       parse_date($nentrydate);
	} else { 
	    # $nstatusid eq "hold"
	    if ($statusid ne "hold") {
	        $CUSTHOLD -= parse_date($entrydate) - 
                    parse_date($nentrydate);
	    }
	}
    } else {  
	# object ids cannot be compared 
	$NOW = time; # time in same format as returned by parse_date
	if ($nstatusid eq "start") {
	    $CUSTHOLD += $NOW - parse_date($nentrydate);
	} else { # $nstatusid eq "hold"
	    if ($statusid ne "hold") {
		$CUSTHOLD -= $NOW - parse_date($nentrydate);
	    }
	}
    }
}
return $CUSTHOLD;