if all your looking for is a unique ID then can't you generate a GUID as the 
ID?  this is more of a question then an answer. not that you would be able to 
use this to sort or order the entries.

Jeffrey Lettau
ERP Systems Manager
polkaudio
________________________________________
From: [EMAIL PROTECTED] [EMAIL PROTECTED] On Behalf Of Buss, Troy (Logitek 
Systems) [EMAIL PROTECTED]
Sent: Thursday, August 28, 2008 7:02 PM
To: [email protected]
Subject: RE: [U2] UniData Keys

-snip-

>- in this instance we
>use unique ids generated using date, system time in milleseconds
(system(12)
>in udt) and pid combined together
>Symeon.

Not a bad idea, however you may encounter problems of losing data in
these 2 areas:

1. As processors get faster, the difference in execution time shortens
and it can be possible to generate the same key during the same
millisecond.   Adding a NAP 1 in my simulated testing eliminated the
duplicates. On one implementation of Pick (Altos?) I recall the
resolution of the system(12) function was only a second.

2. At least one time a year (in my timezone) the clock is turned back
one hour and it would be possible to overwrite existing keys during that
hour.

-Troy
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