Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.misc -> Re: Sequences?

Re: Sequences?

From: Heinz Kiosk <no.spam_at_ntlworld.com>
Date: Wed, 20 Feb 2002 12:05:10 -0000
Message-ID: <mkMc8.91770$as2.14795589@news6-win.server.ntlworld.com>


Steady Tony, that keystroke list just gets longer and longer <G>

"Tony Berrington" <tony.berrington_at_bt.com> wrote in message news:3C73821C.DC0633DF_at_bt.com...
> What happens when someone has the bright idea of saving time by performing
direct loads?
>
> damorgan wrote:
>
> > I disagree with your premise. What most developers do when there are
multiple sources of
> > import is write a before-insert trigger. That way there is no way for
the sequence to
> > not be used appropriately. Now I'll grant it is a few more keystrokes
than 29 ... but
> > then again it looks a lot better on your resume too so you get a
payback.
> >
> > PS: There is no perfect database just as there is no other perfect tool.
I don't care
> > how wonderful a hammer is ... you can't use it to unscrew a bolt.
> >
> > Daniel Morgan
> >
> > Tony Berrington wrote:
> >
> > > Daniel,
> > > I don't think the point is the difficulty of creating the
sequence in the
> > > first place, or in using it.
> > >
> > > The big problem arises when you have several potential sources of
inserts/updates to
> > > your data. You cannot guarantee that they will all use the sequence
(and some may
> > > actually not be able to).
> > >
> > > If you are using it for something as important as key generation, then
you have a
> > > very significant issue.
> > >
> > > By the way, I am an Oracle fan myself. It's a very good database, but
not a perfect
> > > one.
> > >
> > > Tony Berrington
> > >
> > > damorgan wrote:
> > >
> > > > That you haven't needed the capabilities provided by Oracle's
sequences is fine.
> > > > Some people, many people perhaps, don't. But some of us do. And for
us ...
> > > > autonumbering would be useless. So are you saying you'd rather have
something
> > > > that limits you to only one possible usage ... or would you rather
have
> > > > something robust, flexible, and scalable?
> > > >
> > > > But I must state that I find the amount of whining over this to be
amazing. Is
> > > > creating and using a SEQUENCE more difficult than creating an
autonumbered
> > > > column? Lets see:
> > > >
> > > > SQL> CREATE SEQUENCE s;
> > > >
> > > > The total characters typed was 18 including spaces and the
semicolon. that
> > > > created the sequence. I'm a bit sore but I'll continue.
> > > >
> > > > Now I'll add the sequence number to the insert statement for the
table:
> > > >
> > > > s.NEXTVAL,
> > > >
> > > > Well that took a total of 10 keystrokes including the comma at the
end. Probably
> > > > 11 if you hit the space bar before continuing with the rest of the
insert
> > > > statement.
> > > >
> > > > A total of 29 keystrokes.
> > > >
> > > > Damn I guess you are correct ... my fingers are hurting and I'm
developing some
> > > > kind of syndrome that is going to require extensive use of pain
medication,
> > > > antiinflammatory steroids, and physical therapy.
> > > >
> > > > Daniel Morgan
> > > >
> > > > Heinz Kiosk wrote:
> > > >
> > > > > > There is no relationship between MS Access's autonumbering and a
SEQUENCE.
> > > > > The
> > > > > > autonumering is part of the table and is only capable of
sequential
> > > > > numbering.
> > > > > > It has no flexibility, no programmability, and is strictly tied
to a
> > > > > single
> > > > > > table. All it is is the following code built in and hidden from
the end
> > > > > user.
> > > > > >
> > > > > > SELECT MAX(numbering_field)
> > > > > > INTO next_number
> > > > > > FROM xyz;
> > > > > >
> > > > > > INSERT INTO xyz
> > > > > > (numbering_field + 1, other_field1, other_field2)
> > > > > > VALUES
> > > > > > (next_number, someval1, someval2);
> > > > > >
> > > > > > Daniel Morgan
> > > > >
> > > > > Methinks Daniel doth protest too much ;). "All Autonumber/Identity
is" is
> > > > > something exteremely useful that answers 99% of needs for this
kind of
> > > > > thing. I've never wanted numbers that cut across tables and I've
never
> > > > > wanted anything other than incremental numbering in 20 years of db
schema
> > > > > design. I agree "create sequence" is more flexible than MS SQL
identity or
> > > > > MS Access autonumber or DB2 identity or Sybase....(long boring
list of rival
> > > > > technologies snipped); but sequences are also a pain in the arse
when all
> > > > > you want is a system generated identity (as supplied in easier
form by every
> > > > > other db platform I've ever seen). Also are you seriously
suggesting that
> > > > > the above is the algorithm that any db actually uses? I think not.
> > > > > (particularly as you wrote it wrong, SQL syntax error. Also
potential
> > > > > problems with above algorithm with transactions and synchronicity.
Never
> > > > > mind)
> > > > >
> > > > > Regards
>
Received on Wed Feb 20 2002 - 06:05:10 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US