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Diffstat (limited to 'guides/source/active_record_basics.md')
| -rw-r--r-- | guides/source/active_record_basics.md | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/guides/source/active_record_basics.md b/guides/source/active_record_basics.md index 21022f1abb..9d2ba328ea 100644 --- a/guides/source/active_record_basics.md +++ b/guides/source/active_record_basics.md @@ -1,3 +1,5 @@ +**DO NOT READ THIS FILE IN GITHUB, GUIDES ARE PUBLISHED IN http://guides.rubyonrails.org.** + Active Record Basics ==================== @@ -31,7 +33,7 @@ Object Relational Mapping system. in his book _Patterns of Enterprise Application Architecture_. In Active Record, objects carry both persistent data and behavior which operates on that data. Active Record takes the opinion that ensuring -data access logic is part of the object will educate users of that +data access logic as part of the object will educate users of that object on how to write to and read from the database. ### Object Relational Mapping @@ -116,7 +118,7 @@ to Active Record instances: locking](http://api.rubyonrails.org/classes/ActiveRecord/Locking.html) to a model. * `type` - Specifies that the model uses [Single Table - Inheritance](http://api.rubyonrails.org/classes/ActiveRecord/Base.html#label-Single+table+inheritance). + Inheritance](http://api.rubyonrails.org/classes/ActiveRecord/Base.html#class-ActiveRecord::Base-label-Single+table+inheritance). * `(association_name)_type` - Stores the type for [polymorphic associations](association_basics.html#polymorphic-associations). * `(table_name)_count` - Used to cache the number of belonging objects on @@ -310,10 +312,10 @@ models and validate that an attribute value is not empty, is unique and not already in the database, follows a specific format and many more. Validation is a very important issue to consider when persisting to the database, so -the methods `create`, `save` and `update` take it into account when +the methods `save` and `update` take it into account when running: they return `false` when validation fails and they didn't actually perform any operation on the database. All of these have a bang counterpart (that -is, `create!`, `save!` and `update!`), which are stricter in that +is, `save!` and `update!`), which are stricter in that they raise the exception `ActiveRecord::RecordInvalid` if validation fails. A quick example to illustrate: @@ -322,8 +324,9 @@ class User < ActiveRecord::Base validates :name, presence: true end -User.create # => false -User.create! # => ActiveRecord::RecordInvalid: Validation failed: Name can't be blank +user = User.new +user.save # => false +user.save! # => ActiveRecord::RecordInvalid: Validation failed: Name can't be blank ``` You can learn more about validations in the [Active Record Validations @@ -357,7 +360,7 @@ class CreatePublications < ActiveRecord::Migration t.string :publisher_type t.boolean :single_issue - t.timestamps + t.timestamps null: false end add_index :publications, :publication_type_id end |