Re: time/date as key fields

Yep, even timestamps on modern fast boxes will not guarantee uniqueness,
even down to the microsecond. There is an MI timestamp, TOD, that is 8
bytes long and guaranteed to be unique - pretty easily retrieved
(MATTOD) and converted to a 16-character value (CVTHC, or CVTCH - i
forget!) that sorts by date/time. Or you can leave it as its 8-byte
value, that'll still sort just fine.

Vern

On 11/19/2010 4:47 AM, dieter.bender@xxxxxxxxxxxx wrote:

...uniqueness is not guaranteed and the sequence might not be strict. A
transaction number could be addedd automatically and using a view it could
be unvisable to the application.

Dieter



--------------------------------------------------
From: "David FOXWELL"<David.FOXWELL@xxxxxxxxx>
Sent: Friday, November 19, 2010 10:21 AM
To: "Midrange Systems Technical Discussion"<midrange-l@xxxxxxxxxxxx>
Subject: time/date as key fields

Is there anything wrong in using date and time of creation fields already
existing in a transaction table to keep track of transaction history or
would it be advisable to add a separate field transaction_number? The
latter means a lot more program changes.

Thanks

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