Author: danhaywood
Date: Mon Jun 2 08:27:14 2014
New Revision: 1599122
URL: http://svn.apache.org/r1599122
Log:
persistence by reachability
Modified:
isis/site/trunk/content/components/objectstores/jdo/disabling-persistence-by-reachability.md
Modified:
isis/site/trunk/content/components/objectstores/jdo/disabling-persistence-by-reachability.md
URL:
http://svn.apache.org/viewvc/isis/site/trunk/content/components/objectstores/jdo/disabling-persistence-by-reachability.md?rev=1599122&r1=1599121&r2=1599122&view=diff
==============================================================================
---
isis/site/trunk/content/components/objectstores/jdo/disabling-persistence-by-reachability.md
(original)
+++
isis/site/trunk/content/components/objectstores/jdo/disabling-persistence-by-reachability.md
Mon Jun 2 08:27:14 2014
@@ -3,11 +3,11 @@ Title: Disabling Persistence by Reachabi
By default, JDO/DataNucleus supports the concept of
[persistence-by-reachability](http://www.datanucleus.org/products/datanucleus/jdo/orm/cascading.html).
That is, if
a non-persistent entity is associated with an already-persistent entity, then
DataNucleus will detect this and will automatically persist the associated
object. Put another way: there is no need to call Isis'
`DomainObjectContainer#persist(.)` or
`DomainObjectContainer#persistIfNotAlready(.)` methods.
-However, convenient though this feature is, *you may find that it causes
performance issues*.
+However, convenient though this feature is, **you may find that it causes
performance issues**.
One scenario in particular where this performance issues can arise is if your
entities implement the `java.lang.Comparable` interface, and you have used
Isis' [ObjectContracts](../../../reference/Utility.html) utility. The issue
here is that `ObjectContracts` implementation can cause DataNucleus to
recursively rehydrate a larger number of associated entities. (More detail
below).
-We therefore *recommend that you disable persistence-by-reachability*, add the
following to `persistor_datanucleus.properties`:
+We therefore **recommend that you disable persistence-by-reachability**, add
the following to `persistor_datanucleus.properties`:
#
# Require explicit persistence (since entities are Comparable and using
ObjectContracts#compareTo).
