Re: Problem with Sequences in Oracle 8.0.5

Eyvind Elvestrand wrote:
>
> Yes, I just eliminated the CACHE 20
> Use is not very intensive, so I'll try the NOCACHE option -
> otherwise I'll try not to worry!
>
> Thank you!
>
> "Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> skrev i melding
> news:997098611.16455.1.nnrp-01.9e984b29_at_news.demon.co.uk...
> >
> > When you recreated it without cache' do you
> > mean you recreated it using the term NOCACHE
> > explicitly, or did you just eliminate the 'CACHE 20'.
> >
> > In the absence of a specific directive, the default
> > is CACHE 20 - so my guess is that your sequence
> > is still cached.
> >
> > If this is a high usage sequence, you don't really
> > want to make it NOCACHE - the overhead gets
> > a bit high. Also, even with NOCACHE it is still
> > possible to 'lose' values in the data set (e.g. a
> > user acquires the sequence, then rolls back
> > the insert).
> >
> > Don't worry too much about losing values - it's the
> > way sequences work: you can reduce the impact of
> > the problem in your version of Oracle (I think)
> > by adjusting an init.ora parameter called
> > something like 'sequence_cache_entries' (which
> > also happens to default to 20). I think 8.0.5
> > also allows you to use the dbms_pool package
> > to KEEP sequences, again reducing the problem.
> >
> >
> >
> > --
> > Jonathan Lewis
> >
> > Seminars on getting the best out of Oracle
> > Last few places available for Sept 10th/11th
> > See http://www.jlcomp.demon.co.uk/seminar.html
> >
> >
> >
> >
> > Eyvind Elvestrand wrote in message <9klvke$61b$1_at_snipp.uninett.no>...
> > >Have an inventory database running on NT4/Oracle 8.0.5.0.0.
> > >The GUI is programmed in Delphi 5 / Odac (ODI)
> > >For continuous number series I use Oracles's sequence "machinery", like
> > >this:
> > >select SEQ_INV_NR.nextval from DUAL
> > >
> > >Now the select statement has begun returning higher numbers than
 expected -
> > >typically 20 higher!
> > >
> > >Originally the sequence was created like this :
> > >CREATE SEQUENCE SEQ_INV_NR
> > >START WITH 214575
> > >INCREMENT BY 1
> > >NOMAXVALUE
> > >NOCYCLE
> > >CACHE 20
> > >
> > >I suspected the cache part, dropped the sequence and recreated it without
> > >cache - no good.
> > >
> > >Has anybody got a clue!
> > >
> > >Best regards from Eyvind.
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> >

And don't forget that "NOCACHE" = "No performance"

hth
connor

-- 
==============================
Connor McDonald

http://www.oracledba.co.uk

"Some days you're the pigeon, some days you're the statue..."