[jira] [Updated] (JDO-747) Behavior of delete() with multiple concurrent Transactions

["Tilmann Zäschke (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/JDO-747?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Tilmann Zäschke updated JDO-747:
--------------------------------
    Attachment: Ch12-PersistenceManager-No-747.odt

> Behavior of delete() with multiple concurrent Transactions
> ----------------------------------------------------------
>
>                 Key: JDO-747
>                 URL: https://issues.apache.org/jira/browse/JDO-747
>             Project: JDO
>          Issue Type: Improvement
>          Components: specification
>    Affects Versions: JDO 3.1
>            Reporter: Tilmann Zäschke
>            Assignee: Tilmann Zäschke
>            Priority: Minor
>              Labels: concurrency, delete, refresh
>             Fix For: JDO 3.2
>
>         Attachments: Ch12-PersistenceManager-No-747.odt, JDO-StateTransition-logs-2015-12-04.zip, OptimisticCheckConsistency.java, OptimisticFailurePatch_JDO747.txt, StateTransitionPatch_JDO747_v6.txt
>
>
> In the Spec I could not find any statement regarding on how a transaction should behave if an object is deleted in a different concurrent transaction.
> Related Sections are Section 5.8 (how different methods should behave for different object states) and Section 12.6.1 (the behavior of refresh() and related methods).
> For example I wonder about the following situations. Suppose I have two optimistic sessions, pm1 and pm2, both access the same object. pm1 deletes the object and commits. Then what happens in pm2 if:
> 1. pm2 deletes the object and tries to commit, should that work? It's
>    wouldn't be a real conflict if both delete it.
> 2. pm2 modifies the object (make dirty) and calls {{refresh()}}. Should I
>    get an {{ObjectNotFound}} exception?
> 3. pm2 deletes the object and calls {{refresh()}}. According to the spec,
>    {{refresh()}} should not change the object's state. But should it
>    still fail with {{ObjectNotFound}}? If refresh should fail, how can I
>    ever recover from such a situation, because I can't undelete the
>    object?
> Is there a common understanding how this should work? 
> IF there an external definition JDO relies on, then I think a reference to an external document might useful.
> If not, should the Spec define concurrent behavior?



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)