Thread: BUG #6012: Automatically generated sequence number jumps.

BUG #6012: Automatically generated sequence number jumps.

From
"Jai Kumar Shamra"
Date:
The following bug has been logged online:

Bug reference:      6012
Logged by:          Jai Kumar Shamra
Email address:      sharma.jaikumar@gmail.com
PostgreSQL version: 8.4
Operating system:   Windows XP Professional SP2
Description:        Automatically generated sequence number jumps.
Details:

We are facing problem of automatically sequence number changes in increasing
order, why?

Re: BUG #6012: Automatically generated sequence number jumps.

From
"Kevin Grittner"
Date:
"Jai Kumar Shamra" <sharma.jaikumar@gmail.com> wrote:

> Description:        Automatically generated sequence number jumps.

> We are facing problem of automatically sequence number changes in
> increasing order, why?

Probably transactions rolled back or someone used the setval
function.  From the manual:

http://www.postgresql.org/docs/8.4/interactive/functions-sequence.html

| Important: To avoid blocking concurrent transactions that obtain
| numbers from the same sequence, a nextval operation is never
| rolled back; that is, once a value has been fetched it is
| considered used, even if the transaction that did the nextval
| later aborts. This means that aborted transactions might leave
| unused "holes" in the sequence of assigned values. setval
| operations are never rolled back, either.

Of course, you haven't given us a lot of detail from which to draw
conclusions.  If the above doesn't fit with what you're seeing,
please read this and post again:

http://wiki.postgresql.org/wiki/Guide_to_reporting_problems

-Kevin