You are viewing a plain text version of this content. The canonical link for it is here.
Posted to derby-dev@db.apache.org by "Rick Hillegas (JIRA)" <ji...@apache.org> on 2011/06/24 20:27:47 UTC

[jira] [Updated] (DERBY-5151) Don't leak unused identity/sequence values on abnormal exit.

     [ https://issues.apache.org/jira/browse/DERBY-5151?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Rick Hillegas updated DERBY-5151:
---------------------------------

    Description: 
Currently, a sequence in Derby always uses a pre allocating cache. I'm working on an usecase which requires a number to increase with a fixed value. The usecase fails after a restart because of the pre allocating cache.

I've created a patch that adds the options CACHE | NO CACHE to the create sequence statement. When no cache is provided, the pre allocating cache size will be set to 1, which results in a "no cache sequence".
I've followed the CYCLE | NO CYCLE code as much as possible. Tested it in my own app and it seems to work fine.

RH: Note that part of this issue has been addressed by the work on DERBY-4437. Sequence values will NOT leak now if you perform an orderly shutdown of your database. However, values still leak if the VM exits before the database has been shutdown. I have changed this issue's title to indicate that the remaining work applies to both sequences and identity columns.

  was:
Currently, a sequence in Derby always uses a pre allocating cache. I'm working on an usecase which requires a number to increase with a fixed value. The usecase fails after a restart because of the pre allocating cache.

I've created a patch that adds the options CACHE | NO CACHE to the create sequence statement. When no cache is provided, the pre allocating cache size will be set to 1, which results in a "no cache sequence".
I've followed the CYCLE | NO CYCLE code as much as possible. Tested it in my own app and it seems to work fine.

        Summary: Don't leak unused identity/sequence values on abnormal exit.  (was: Sequence without cache)

> Don't leak unused identity/sequence values on abnormal exit.
> ------------------------------------------------------------
>
>                 Key: DERBY-5151
>                 URL: https://issues.apache.org/jira/browse/DERBY-5151
>             Project: Derby
>          Issue Type: Improvement
>          Components: SQL
>            Reporter: Mark Holster
>         Attachments: sequence-no-cache.patch
>
>
> Currently, a sequence in Derby always uses a pre allocating cache. I'm working on an usecase which requires a number to increase with a fixed value. The usecase fails after a restart because of the pre allocating cache.
> I've created a patch that adds the options CACHE | NO CACHE to the create sequence statement. When no cache is provided, the pre allocating cache size will be set to 1, which results in a "no cache sequence".
> I've followed the CYCLE | NO CYCLE code as much as possible. Tested it in my own app and it seems to work fine.
> RH: Note that part of this issue has been addressed by the work on DERBY-4437. Sequence values will NOT leak now if you perform an orderly shutdown of your database. However, values still leak if the VM exits before the database has been shutdown. I have changed this issue's title to indicate that the remaining work applies to both sequences and identity columns.

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira