I would argue (it is my nature) that 1/100 second is not enough.
damorgan <dan.morgan_at_ci.seattle.wa.us> wrote in message
news:3C756B35.2FFC9D6C_at_ci.seattle.wa.us...
> You can also use DBMS_UTILITY.GET_TIME() to return 1/100ths of a second
for
> more granularity.
>
> Daniel Morgan
>
>
>
> Keith Boulton wrote:
>
> > Sybrand Bakker <postbus_at_sybrandb.demon.nl> wrote in message
> > news:3koa7u0fh6uhhs69c1n14glq9cqg1716r7_at_4ax.com...
> > > On Thu, 21 Feb 2002 13:18:25 -0700, "Leigh Gold" <intan_5ee_at_yahoo.com>
> > > wrote:
> > >
> > > >What is the risk involved in using sequence number to keep track of
the
> > last
> > > >record in a table?
> > > >
> > > >We use a table to keep history of an event, everytime an event
changes,
> > we
> > > >insert a row in this history table with a sequence number as its
primary
> > key
> > > >and information about this event. We are basing our query on
> > max(sequence)
> > > >to track the last time this event occurred. For some reason, the
> > developer
> > > >refuses to use sysdate for this purpose.
> > > >
> > > >Is there any risk involved in using the method?
> > > >
> > > >Thanks,
> > > >
> > > >Leigh
> > > >
> > > >
> > > >
> > > Loosing sequence numbers is inevitable using the cache option (which
> > > is the default) I'm not sure this won't happen with the nocache
> > > option. However, I never use that as the sequence number is supposed
> > > to be meaningless, and your sequence number should be meaningful.
> > > Probably hiring a different developer will be cheaper in the long run.
> > >
> > Except that the current developer is right - dates are precise only to
the
> > second and it is very easy to generate more than 1 event per second.
> >
> > The use of sequences for this purpose is reasonable, I believe, given
only
> > that OPS is not used since multiple instances of the sequence exist so
the
> > allocation of sequence numbers does not occur sequentially (eh?). You
also
> > have to ensure that the sequence will never wrap.
>
Received on Thu Feb 21 2002 - 16:56:48 CST
