RE: Timestamp field

[James David Rich <james@xxxxxxxxxxxxx>]

On Thu, 20 Jan 2000, Buck Calabro wrote:
> Marc,
> I would not depend on using the timestamp as a unique key.  As you have
> found out, on a sufficiently fast enough machine you can get duplicates.
> The upshot of this is that even if it works today, when the next generation
> of CPUs come out it might fail.
> 
> I would suggest adding another field (sequence number) if you have a need to
> discriminate between each record.  If you really truly need the extra three
> digits, consider using SQL to do your insert, as in: 
> insert into xxx (field, timstp) values(:field, CURRENT TIMESTAMP)

If a unique key is needed and it can be any number how about duplicating
something like what MySQL does?  You can define a field as INT
AUTO_INCREMENT PRIMARY KEY.  I think you can do something like this in RPG
by creating a field in your database file that is say 10,0 (or however big
you need it) and make it the unique key.  Then when you want to add
another record to the file lock the file, read previous, add 1, write the
new record, and release the file.

James Rich
james@dansfoods.com

+---
| This is the RPG/400 Mailing List!
| To submit a new message, send your mail to RPG400-L@midrange.com.
| To subscribe to this list send email to RPG400-L-SUB@midrange.com.
| To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---