db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "ASF subversion and git services (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (DERBY-532) Support deferrable constraints
Date Wed, 11 Dec 2013 23:10:08 GMT

    [ https://issues.apache.org/jira/browse/DERBY-532?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13845815#comment-13845815
] 

ASF subversion and git services commented on DERBY-532:
-------------------------------------------------------

Commit 1550308 from [~dagw] in branch 'code/trunk'
[ https://svn.apache.org/r1550308 ]

DERBY-532 Support deferrable constraints

Patch derby-532-test-speedup changes ConstraintCharacteristicsTest to
use a main memory database for some tests for increased speed. It also
changes the way SystemPropertyTestSetup for static properties closes
down the database to not deregister the driver; without this change we
saw a test setup try to connect via the client driver to a Derby server
engine without a registered driver.

> Support deferrable constraints
> ------------------------------
>
>                 Key: DERBY-532
>                 URL: https://issues.apache.org/jira/browse/DERBY-532
>             Project: Derby
>          Issue Type: Improvement
>          Components: SQL
>            Reporter: Jörg von Frantzius
>            Assignee: Dag H. Wanvik
>              Labels: derby_triage10_11
>         Attachments: IndexDescriptor.html, IndexDescriptorImpl.html, IndexRowGenerator.html,
SortObserver.html, deferredConstraints.html, deferredConstraints.html, deferredConstraints.html,
deferredConstraints.html, deferredConstraints.html, derby-532-fix-drop-not-nullable.diff,
derby-532-fix-drop-not-nullable.status, derby-532-fix-metadata-1.diff, derby-532-fix-metadata-1.status,
derby-532-import-1.diff, derby-532-import-1.status, derby-532-import-2.diff, derby-532-import-3.diff,
derby-532-import-3.status, derby-532-more-tests-1.diff, derby-532-more-tests-1.stat, derby-532-nullableUniqueFix.diff,
derby-532-nullableUniqueFix.status, derby-532-post-scan-1.diff, derby-532-post-scan-1.stat,
derby-532-post-scan-2.diff, derby-532-post-scan-2.stat, derby-532-post-scan-3.diff, derby-532-post-scan-3.stat,
derby-532-post-scan-4.diff, derby-532-post-scan-4.stat, derby-532-serializable-scan-1.diff,
derby-532-serializable-scan-2.diff, derby-532-serializable-scan-2.stat, derby-532-syntax-binding-dict-1.diff,
derby-532-syntax-binding-dict-1.status, derby-532-syntax-binding-dict-2.diff, derby-532-syntax-binding-dict-2.status,
derby-532-syntax-binding-dict-all-1.diff, derby-532-test-speedup.diff, derby-532-test-speedup.status,
derby-532-test-with-default-deferrable-all-over.diff, derby-532-testAlterConstraintInvalidation.diff,
derby-532-testAlterConstraintInvalidation.status, derby-532-unique-pk-1.diff, derby-532-unique-pk-1.status,
derby-532-unique-pk-2.diff, derby-532-unique-pk-3.diff, derby-532-unique-pk-3.status, derby-532-xa-1.diff,
derby-532-xa-2.diff, derby-532-xa-3.diff, derby-532-xa-3.status
>
>
> In many situations it is desirable to have constraints checking taking place only at
transaction commit time, and not before. If e.g. there is a chain of foreign key constraints
between tables, insert statements have to be ordered to avoid constraint violations. If foreign
key references are circular, the DML has to be split into insert statements and subsequent
update statements by the user.
> In other words, with deferred constraints checking, life is much easier for the user.
Also it can create problems with softwares such as object-relational mapping tools that are
not prepared for statement ordering and thus depend on deferred constraints checking.



--
This message was sent by Atlassian JIRA
(v6.1.4#6159)

Mime
View raw message