Re: Sequence Numbers Jumping

From: Robert Klemme <>
Date: Wed, 05 Mar 2008 18:47:46 +0100
Message-ID: <>

On 05.03.2008 16:13, Ken Denny wrote:

> On Mar 5, 6:36 am, Flash Gordon <> wrote:

>> We are migrating an application from Oracle 9 to Oracle 10. The
>> application uses several sequence objects for user visible sequences.
>> For some reason on Oracle 10 the sequences are jumping. I've checked
>> that the sequences are defined as ordered and tried disabling the
>> caching (a desperation measure as I don't believe it could be that).
>> Any suggestions as to what could be causing this in Oracle 10 when it
>> did not occur in Oracle 9? Any suggestions as to how to investigate this
>> as I am new to Oracle?
>> --
>> Flash Gordon
> What do you mean by jumping? You mean there are gaps? There will
> always be gaps when using a sequence. I don't know how you managed to
> not have gaps using 9. If gaps are not acceptable then you can't use
> sequences.

Adding to that these are the reasons why you can get gaps:

  • caching enabled and sessions close without using all values cached so far
  • rollbacks on TX that inserted sequence values
  • deletions

Did I miss one?


        robert Received on Wed Mar 05 2008 - 11:47:46 CST

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