I would:

• fork database update
• return page to browser with JS that calls a monitor script - use setTimeout()

When database is updating, it sets a percentage mark - eg, 20,000 records, % mark is 200 ($percent_mark = int($total/100);

create a temp file. Every $percent_mark records, append a character to the file.

Return a marker for the temp file in the cgi response, so the JavaScript call points to correct file:

<SCRIPT LANGUAGE="JavaScript>
setTimeout(30000,"top.display_frame.location.href= 'counter.cgi?tmpfil
+e=temp_file_name';");
</SCRIPT>
[download]

Then, when you call the counter.cgi file, percentage complete is:

my $percent_complete = stat(temp_file_name)[7];
[download]

Return this in your display frame along with JS above.

Amend to suit - only my .02

cLive ;-)

PS - if it really takes an hour, you might want to set a cookie and tell them to check back later - and use the cookie to identify them in the script.