[
https://issues.apache.org/jira/browse/OPENJPA-235?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Gokhan Ergul updated OPENJPA-235:
---------------------------------
Attachment: merge-detached.patch
merge-multigen-collection-testcase.zip
Reece,
I'm sorry it took so long, somehow I managed to mess up maven plugin repo,
wasn't able to run tests at all for the last week. Testcases attached, they're
ready to be used as part of standard openjpa tests.
TestMultigenOneToManyMerge.updateDetached should succeed with the patch I
attached. TestMultigenOneToManyMerge.updateAttached works with auto-generated
tables against Derby, fails against mysql/innodb with foreign keys defined
between tables, that's the case I'm hoping your patch would solve.
Let me know if you have trouble setting up/running the tests.
Gokhan.
> SQL reordering to avoid non-nullable foreign key constraint violations
> ----------------------------------------------------------------------
>
> Key: OPENJPA-235
> URL: https://issues.apache.org/jira/browse/OPENJPA-235
> Project: OpenJPA
> Issue Type: Improvement
> Components: kernel
> Reporter: Reece Garrett
> Assignee: Patrick Linskey
> Fix For: 0.9.8
>
> Attachments: merge-detached.patch,
> merge-multigen-collection-testcase.zip, openjpa-235-test.jar,
> openjpa-235-test1.jar, sqlreorder.patch, sqlReorder2.patch
>
>
> OpenJPA does not do any SQL statement re-ordering in order to resolve foreign
> key constraints. Instead, objects are always inserted in the order in which
> the user persists the instances. When you persist in an order that would
> violate foreign key constraints, OpenJPA attempts to insert null and then
> update the foreign key value in a separate statement. If you use non-nullable
> constraints, though, you must persist your objects in the correct order.
> This improvement re-orders SQL statements as follows:
> 1. First, all insert statements execute. Inserts which have foreign keys with
> non-nullable constraints execute AFTER the foreign keys which they depend on
> have been inserted since no deferred update is possible.
> 2. Next, all update statements execute. No reordering is necessary.
> 3. Finally, all delete statements execute. Like inserts, deletes execute in
> an order which does not violate non-nullable foreign key constraints.
> If a circular foreign key reference is found during the re-ordering process
> then re-ordering halts and the remaining unordered statements are left as is.
> There is nothing that can be done about the circular reference (other than
> fixing the schema) and the resulting SQL statements will not succeed.
> The net effect is that users do not need to worry about the persistence order
> of their objects regardless of non-nullable foreign key constraints. The only
> class modified was
> org.apache.openjpa.jdbc.kernel.OperationOrderUpdateManager. I have included a
> patch which includes my modifications to OperationOrderUpdateManager and test
> cases. The test cases I have provided fail on the current trunk but pass with
> my modifications. I have also verified that I did not break anything by using
> maven to run all test cases with my modifications in place.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
