fixup for stringify that can be false in find_or_create_related

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / Relationship / Base.pm

diff --git a/lib/DBIx/Class/Relationship/Base.pm b/lib/DBIx/Class/Relationship/Base.pm
index 96b7c18..05f4c52 100644 (file)
--- a/lib/DBIx/Class/Relationship/Base.pm
+++ b/lib/DBIx/Class/Relationship/Base.pm
@@ -29,27 +29,42 @@ methods, for predefined ones, look in L<DBIx::Class::Relationship>.
 
   __PACKAGE__->add_relationship('relname', 'Foreign::Class', $cond, $attrs);
 
-The condition needs to be an SQL::Abstract-style representation of the
-join between the tables. When resolving the condition for use in a JOIN,
-keys using the pseudo-table I<foreign> are resolved to mean "the Table on the
-other side of the relationship", and values using the pseudo-table I<self>
+The condition needs to be an L<SQL::Abstract>-style representation of the
+join between the tables. When resolving the condition for use in a C<JOIN>,
+keys using the pseudo-table C<foreign> are resolved to mean "the Table on the
+other side of the relationship", and values using the pseudo-table C<self>
 are resolved to mean "the Table this class is representing". Other
 restrictions, such as by value, sub-select and other tables, may also be
-used. Please check your database for JOIN parameter support.
+used. Please check your database for C<JOIN> parameter support.
 
-For example, if you're creating a rel from Author to Book, where the Book
-table has a column author_id containing the ID of the Author row:
+For example, if you're creating a relationship from C<Author> to C<Book>, where
+the C<Book> table has a column C<author_id> containing the ID of the C<Author>
+row:
 
   { 'foreign.author_id' => 'self.id' }
 
-will result in the JOIN clause
+will result in the C<JOIN> clause
 
-  author me JOIN book book ON bar.author_id = me.id
+  author me JOIN book book ON book.author_id = me.id
 
-You can specify as many foreign => self mappings as necessary. Each key/value
-pair provided in a hashref will be used as ANDed conditions, to add an ORed
-condition, use an arrayref of hashrefs. See the L<SQL::Abstract> documentation
-for more details.
+For multi-column foreign keys, you will need to specify a C<foreign>-to-C<self>
+mapping for each column in the key. For example, if you're creating a
+relationship from C<Book> to C<Edition>, where the C<Edition> table refers to a
+publisher and a type (e.g. "paperback"):
+
+  {
+    'foreign.publisher_id' => 'self.publisher_id',
+    'foreign.type_id'      => 'self.type_id',
+  }
+
+This will result in the C<JOIN> clause:
+
+  book me JOIN edition edition ON edition.publisher_id = me.publisher_id
+    AND edition.type_id = me.type_id
+
+Each key-value pair provided in a hashref will be used as C<AND>ed conditions.
+To add an C<OR>ed condition, use an arrayref of hashrefs. See the
+L<SQL::Abstract> documentation for more details.
 
 Valid attributes are as follows:
 
@@ -97,7 +112,7 @@ created, which calls C<create_related> for the relationship.
 =back
 
 Registers a relationship on the class. This is called internally by
-L<DBIx::Class::ResultSourceProxy> to set up Accessors and Proxies.
+DBIx::Class::ResultSourceProxy to set up Accessors and Proxies.
 
 =cut
 
@@ -249,7 +264,8 @@ L<DBIx::Class::ResultSet/"find_or_create"> for details.
 
 sub find_or_create_related {
   my $self = shift;
-  return $self->find_related(@_) || $self->create_related(@_);
+  my $obj = $self->find_related(@_);
+  return (defined($obj) ? $obj : $self->create_related(@_));
 }
 
 =head2 set_from_related