Release 0.07035

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

diff --git a/lib/DBIx/Class/Schema/Loader/Base.pm b/lib/DBIx/Class/Schema/Loader/Base.pm
index 0be9dba..31221e6 100644 (file)
--- a/lib/DBIx/Class/Schema/Loader/Base.pm
+++ b/lib/DBIx/Class/Schema/Loader/Base.pm
@@ -29,7 +29,7 @@ use List::MoreUtils qw/all any firstidx uniq/;
 use File::Temp 'tempfile';
 use namespace::clean;
 
-our $VERSION = '0.07031';
+our $VERSION = '0.07035';
 
 __PACKAGE__->mk_group_ro_accessors('simple', qw/
                                 schema
@@ -389,17 +389,20 @@ override the introspected attributes of the foreign key if any.
 For example:
 
   relationship_attrs => {
-    has_many => { cascade_delete => 1, cascade_copy => 1 },
+    has_many   => { cascade_delete => 1, cascade_copy => 1 },
+    might_have => { cascade_delete => 1, cascade_copy => 1 },
   },
 
 use this to turn L<DBIx::Class> cascades to on on your
-L<has_many|DBIx::Class::Relationship/has_many> relationships, they default to
-off.
+L<has_many|DBIx::Class::Relationship/has_many> and
+L<might_have|DBIx::Class::Relationship/might_have> relationships, they default
+to off.
 
 Can also be a coderef, for more precise control, in which case the coderef gets
-this hash of parameters:
+this hash of parameters (as a list:)
 
     rel_name        # the name of the relationship
+    rel_type        # the type of the relationship: 'belongs_to', 'has_many' or 'might_have'
     local_source    # the DBIx::Class::ResultSource object for the source the rel is *from*
     remote_source   # the DBIx::Class::ResultSource object for the source the rel is *to*
     local_table     # a DBIx::Class::Schema::Loader::Table object for the table of the source the rel is from
@@ -416,6 +419,7 @@ For example:
         my %p = @_;
 
         say "the relationship name is: $p{rel_name}";
+        say "the relationship is a: $p{rel_type}";
         say "the local class is: ",  $p{local_source}->result_class;
         say "the remote class is: ", $p{remote_source}->result_class;
         say "the local table is: ", $p{local_table}->sql_name;
@@ -430,6 +434,50 @@ For example:
         }
     },
 
+These are the default attributes:
+
+    has_many => {
+        cascade_delete => 0,
+        cascade_copy   => 0,
+    },
+    might_have => {
+        cascade_delete => 0,
+        cascade_copy   => 0,
+    },
+    belongs_to => {
+        on_delete => 'CASCADE',
+        on_update => 'CASCADE',
+        is_deferrable => 1,
+    },
+
+For L<belongs_to|DBIx::Class::Relationship/belongs_to> relationships, these
+defaults are overridden by the attributes introspected from the foreign key in
+the database, if this information is available (and the driver is capable of
+retrieving it.)
+
+This information overrides the defaults mentioned above, and is then itself
+overridden by the user's L</relationship_attrs> for C<belongs_to> if any are
+specified.
+
+In general, for most databases, for a plain foreign key with no rules, the
+values for a L<belongs_to|DBIx::Class::Relationship/belongs_to> relationship
+will be:
+
+    on_delete     => 'NO ACTION',
+    on_update     => 'NO ACTION',
+    is_deferrable => 0,
+
+In the cases where an attribute is not supported by the DB, a value matching
+the actual behavior is used, for example Oracle does not support C<ON UPDATE>
+rules, so C<on_update> is set to C<NO ACTION>. This is done so that the
+behavior of the schema is preserved when cross deploying to a different RDBMS
+such as SQLite for testing.
+
+In the cases where the DB does not support C<DEFERRABLE> foreign keys, the
+value is set to C<1> if L<DBIx::Class> has a working C<<
+$storage->with_deferred_fk_checks >>. This is done so that the same
+L<DBIx::Class> code can be used, and cross deployed from and to such databases.
+
 =head2 debug
 
 If set to true, each constructive L<DBIx::Class> statement the loader
@@ -570,6 +618,10 @@ If it is a coderef, the argument passed will be a hashref of this form:
         remote_class   => name of the DBIC class we are related to,
         remote_moniker => moniker of the DBIC class we are related to,
         remote_columns => columns in the other table in the relationship,
+        # for type => "many_to_many" only:
+        link_class     => name of the DBIC class for the link table
+        link_moniker   => moniker of the DBIC class for the link table
+        link_rel_name  => name of the relationship to the link table
     }
 
 DBICSL will try to use the value returned as the relationship name.