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Diffstat (limited to 'railties/guides/source/migrations.textile')
-rw-r--r-- | railties/guides/source/migrations.textile | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/railties/guides/source/migrations.textile b/railties/guides/source/migrations.textile index 4c49a4ccbc..0d13fbc10a 100644 --- a/railties/guides/source/migrations.textile +++ b/railties/guides/source/migrations.textile @@ -584,13 +584,11 @@ h3. Active Record and Referential Integrity The Active Record way claims that intelligence belongs in your models, not in the database. As such, features such as triggers or foreign key constraints, which push some of that intelligence back into the database, are not heavily used. -Validations such as +validates_uniqueness_of+ are one way in which models can enforce data integrity. The +:dependent+ option on associations allows models to automatically destroy child objects when the parent is destroyed. Like anything which operates at the application level these cannot guarantee referential integrity and so some people augment them with foreign key constraints. +Validations such as +validates :foreign_key, :uniqueness => true+ are one way in which models can enforce data integrity. The +:dependent+ option on associations allows models to automatically destroy child objects when the parent is destroyed. Like anything which operates at the application level these cannot guarantee referential integrity and so some people augment them with foreign key constraints. Although Active Record does not provide any tools for working directly with such features, the +execute+ method can be used to execute arbitrary SQL. There are also a number of plugins such as "foreign_key_migrations":http://github.com/harukizaemon/redhillonrails/tree/master/foreign_key_migrations/ which add foreign key support to Active Record (including support for dumping foreign keys in +db/schema.rb+). h3. Changelog -"Lighthouse ticket":http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/6 - * July 15, 2010: minor typos corrected by "Jaime Iniesta":http://jaimeiniesta.com * September 14, 2008: initial version by "Frederick Cheung":credits.html#fcheung |