be more explicit in explanation of <join>

git-svn-id: https://svn.jboss.org/repos/hibernate/trunk/Hibernate3/doc@5736 1b8cb986-b30d-0410-93ca-fae66ebed9b2
This commit is contained in:
Gavin King 2005-02-15 00:32:36 +00:00
parent 1d0212fee7
commit 2d13026078
1 changed files with 9 additions and 4 deletions

View File

@ -2194,9 +2194,14 @@
<callout arearefs="join4">
<para>
<literal>fetch</literal> (optional - defaults to <literal>join</literal>):
If set to <literal>select</literal> for a join defined on a subclass, then rather
than joining, a sequential select will be issued only if a row turns out to represent
an instance of the subclass.
If set to <literal>join</literal>, the default, Hibernate will use an inner join
to retrieve a <literal>&lt;join&gt;</literal> defined by a class or its superclasses
and an outer join for a <literal>&lt;join&gt;</literal> defined by a subclass.
If set to <literal>select</literal> then Hibernate will use a sequential select for
a <literal>&lt;join&gt;</literal> defined on a subclass, which will be issued only
if a row turns out to represent an instance of the subclass. Inner joins will still
be used to retrieve a <literal>&lt;join&gt;</literal> defined by the class and its
superclasses.
</para>
</callout>
<callout arearefs="join5">
@ -2210,7 +2215,7 @@
<para>
<literal>optional</literal> (optional - defaults to <literal>false</literal>):
If enabled, Hibernate will insert a row only if the properties defined by this
join are non-null .
join are non-null and will always use an outer join to retrieve the properties.
</para>
</callout>
</calloutlist>