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OPENJPA-2099: doc for openjpa.jdbc.CachesSelect option 

git-svn-id: https://svn.apache.org/repos/asf/openjpa/trunk@1241509 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Pinaki Poddar 2012-02-07 16:23:51 +00:00
parent e5a7710d6b
commit 647ab63101
2 changed files with 62 additions and 0 deletions
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25
openjpa-project/src/doc/manual/ref_guide_caching.xml
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@ -1351,4 +1351,29 @@ for a JPQL query.
</para>
</section>
<section id="ref_guide_cache_select">
<title>Select Cache</title>
<indexterm zone="ref_guide_cache_select">
<primary>caching</primary>
<secondary>Select Cache</secondary>
</indexterm>
<para>
OpenJPA generates SQL SELECT statements to fetch database records and populates the persistent entity states
from the result data. Under certain assumptions, these select statements are invariant for an entity
or its relations except that their binding parameters vary between executions. In version 2.2.0, OpenJPA
allows these select statements be reused. Such reuse avoids the cost of regenerating these statements in
every execution.
</para>
<para>
This facility can be activated by <programlisting>openjpa.jdbc.CachesSelect</programlisting> configuration
property. This property accepts boolean value of <programlisting>true</programlisting> or
<programlisting>false</programlisting>. By default, the property value is <programlisting>false</programlisting>.
The property value can be changed once and only once.
</para>
<para>
The assumption that a select statement for a persistent entity is invariant holds only if the fetch plan
is not dynamically modified. OpenJPA runtime currently makes no attempt to ensure that the assumption
is held true i.e. the application is not modifying the fetch plan dynamically.
</para>
</section>
</chapter>

37
openjpa-project/src/doc/manual/ref_guide_conf.xml
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@ -3427,6 +3427,43 @@ levels are equivalent. Lock levels <literal>pessimistic-read</literal>,
<para>
The following properties apply exclusively to the OpenJPA JDBC back-end.
</para>
<section id="openjpa.jdbc.CachesSelect">
<title>
openjpa.jdbc.CachesSelect
</title>
<indexterm zone="openjpa.jdbc.CachesSelect">
<primary>
Select Cache
</primary>
</indexterm>
<indexterm zone="openjpa.jdbc.CachesSelect">
<primary>
caching
</primary>
<secondary>
Select Cache
</secondary>
</indexterm>
<para>
<emphasis role="bold">Property name:</emphasis>
<literal>openjpa.jdbc.CachesSelect</literal>
</para>
<para>
<emphasis role="bold">Resource adaptor config-property:</emphasis>
<literal>CachesSelect</literal>
</para>
<para>
<emphasis role="bold">Default:</emphasis> <literal>false</literal>.
</para>
<para>
<emphasis role="bold">Description:</emphasis> A plugin string (see
<xref linkend="ref_guide_conf_plugins"/>) describing the options to reuse SQL SELECT
statements generated to load persistent entity and its relations.
See <xref linkend="ref_guide_cache_select"/> for details.
</para>
</section>
<section id="openjpa.jdbc.ConnectionDecorators">
<title>
openjpa.jdbc.ConnectionDecorators