Re: Sequence Number Re-use is it possible, what is the standard

"Sybrand Bakker" <postbus_at_sybrandb.demon.nl> a écrit dans le message news: 57fq9tkfvmsqnsja55sd70o6blbq2dt33d_at_4ax.com...
> On Wed, 28 Feb 2001 16:59:37 GMT,
> u28656005_at_spawnkill.ip-mobilphone.net wrote:
>
> >We have a system that uses a Sequence table to get id's for our bids.
> >
> >In our application the user might click new, which gets the nextval.
> >
> >But if they click new again, or they close the program, we obviously
> >
> >lose that number from the sequence table. What do most people do about
> >
> >this. We really don't want to lose this number, and there will
> >
> >eventually be over 200 users getting unique id's from our sequence. So
> >
> >unused numbers can go pretty rapidly.
> >
> >Has anyone done something like, put the unused numbers into a table,
> >
> >have the program first look to see if there are any record in this
> >
> >table, and grab one of these numbers and uses it, and if they find no
> >
> >records it goes to the sequence table. Is this a stupid idea?
> >
> >
> >
> >Inquiring minds want to know
> >
> >Thank you very much for your help.
> >
> >
> >
> >Mark
> >
> Use the nocache option of the create sequence command, which will at
> least take away the buffer of pre-created sequence numbers, and for
> the rest : don't bother. The maximum sequence number is 2^32 -1, which
> you probably won't even reach before you retire.
>
> Hth,
>
>
> Sybrand Bakker, Oracle DBA

I agree with Sybrand except for the maximum sequence number which

is 999999999999999999999999999 in Oracle7 and 10**27 with Oracle8i.

--
Cheers
Michel