Re: Duplicate timestamp(6): How is this possible?

Not that I'm involved in building systems anymore but is there no longer
required to use a sequence to guarantee a unique id for a record?

On 20 January 2011 08:42, Dunbar, Norman (Capgemini) <
norman.dunbar.capgemini@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

> Morning Michael,
>
> >> I believe I may have figured this out. I am using
> >> current_timestamp. I believe that for a given moment in
> >> time, this value could be different depending on the
> >> location of the user. 'believe' because I'm not really sure.
>
> Current_timestamp is the "session" timestamp (actually, TIMESTAMP WITH
> TIME ZONE) and as such can be duplicated due to the same time being hit
> in two different timezones.
>
>
> >> I think that if I change the default to SYSTIMESTAMP, the
> >> local server timestamp will be populated.
>
> It will, regardless of where the users are located. SYSTIMESTAMP is
> always the database server time. Unless you get really "lucky" you
> shouldn't have duplicates. SYSTIMESTAMP is also a TIMESTAMP WITH TIME
> ZONE.
>
>
>
> Cheers,
> Norm.
>
> Norman Dunbar
> Contract Senior Oracle DBA
> Capgemini Database Team (EA)
> Internal : 7 28 2051
> External : 0113 231 2051
>
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-- 
Howard A. Latham

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