Author: gsim
Date: Thu Jul 8 09:30:38 2010
New Revision: 961666
URL: http://svn.apache.org/viewvc?rev=961666&view=rev
Log:
Improved section on transactions
Modified:
qpid/trunk/qpid/doc/book/src/Programming-In-Apache-Qpid.xml
Modified: qpid/trunk/qpid/doc/book/src/Programming-In-Apache-Qpid.xml
URL:
http://svn.apache.org/viewvc/qpid/trunk/qpid/doc/book/src/Programming-In-Apache-Qpid.xml?rev=961666&r1=961665&r2=961666&view=diff
==============================================================================
--- qpid/trunk/qpid/doc/book/src/Programming-In-Apache-Qpid.xml (original)
+++ qpid/trunk/qpid/doc/book/src/Programming-In-Apache-Qpid.xml Thu Jul 8
09:30:38 2010
@@ -2207,19 +2207,22 @@ connection.setOption("protocol", "ssl");
<section>
<title>Transactions</title>
- <para>In AMQP, transactions cover the semantics of enqueues and
- dequeues.</para>
- <para>When sending messages, a transaction tracks enqueues
- without actually delivering the messages, a commit places
- messages on their queues, and a rollback discards the
- enqueues.</para>
-
- <para>When receiving messages, a transaction tracks dequeues
- without actually removing acknowledged messages, a commit
- removes all acknowledged messages, and a rollback discards
- acknowledgements. A rollback does not release the message, it
- must be explicitly released to return it to the queue.</para>
+ <para>Sometimes it is useful to be able to group messages
+ transfers - sent and/or received - on a session into atomic
+ grouping. This can be done be creating the session as
+ transactional. On a transactional session sent messages only
+ become available at the target address on commit. Likewise any
+ received and acknowledged messages are only discarded at their
+ source on commit
+
+ <footnote><para>Note that this currently is only true for
+ messages received using a reliable mode
+ e.g. at-least-once. Messages sent by a broker to a receiver in
+ unreliable receiver will be discarded immediately regardless of
+ transctionality.</para></footnote>
+
+ .</para>
<example>
<title>Transactions</title>
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