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If your database supports setting the isolation level for a transaction, you can set it like so: Post.transaction(isolation: :serializable) do # ... end Valid isolation levels are: * `:read_uncommitted` * `:read_committed` * `:repeatable_read` * `:serializable` You should consult the documentation for your database to understand the semantics of these different levels: * http://www.postgresql.org/docs/9.1/static/transaction-iso.html * https://dev.mysql.com/doc/refman/5.0/en/set-transaction.html An `ActiveRecord::TransactionIsolationError` will be raised if: * The adapter does not support setting the isolation level * You are joining an existing open transaction * You are creating a nested (savepoint) transaction The mysql, mysql2 and postgresql adapters support setting the transaction isolation level. However, support is disabled for mysql versions below 5, because they are affected by a bug (http://bugs.mysql.com/bug.php?id=39170) which means the isolation level gets persisted outside the transaction.
833 lines
27 KiB
Markdown
833 lines
27 KiB
Markdown
## Rails 4.0.0 (unreleased) ##
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* Support for specifying transaction isolation level
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If your database supports setting the isolation level for a transaction, you can set
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it like so:
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Post.transaction(isolation: :serializable) do
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# ...
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end
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Valid isolation levels are:
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* `:read_uncommitted`
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* `:read_committed`
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* `:repeatable_read`
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* `:serializable`
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You should consult the documentation for your database to understand the
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semantics of these different levels:
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* http://www.postgresql.org/docs/9.1/static/transaction-iso.html
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* https://dev.mysql.com/doc/refman/5.0/en/set-transaction.html
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An `ActiveRecord::TransactionIsolationError` will be raised if:
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* The adapter does not support setting the isolation level
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* You are joining an existing open transaction
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* You are creating a nested (savepoint) transaction
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The mysql, mysql2 and postgresql adapters support setting the transaction
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isolation level. However, support is disabled for mysql versions below 5,
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because they are affected by a bug (http://bugs.mysql.com/bug.php?id=39170)
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which means the isolation level gets persisted outside the transaction.
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*Jon Leighton*
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* `ActiveModel::ForbiddenAttributesProtection` is included by default
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in Active Record models. Check the docs of `ActiveModel::ForbiddenAttributesProtection`
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for more details.
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*Guillermo Iguaran*
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* Remove integration between Active Record and
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`ActiveModel::MassAssignmentSecurity`, `protected_attributes` gem
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should be added to use `attr_accessible`/`attr_protected`. Mass
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assignment options has been removed from all the AR methods that
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used it (ex. `AR::Base.new`, `AR::Base.create`, `AR::Base#update_attributes`, etc).
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*Guillermo Iguaran*
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* Fix the return of querying with an empty hash.
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Fix #6971.
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User.where(token: {})
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Before:
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#=> SELECT * FROM users;
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After:
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#=> SELECT * FROM users WHERE 1 = 2;
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*Damien Mathieu*
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* Fix creation of through association models when using `collection=[]`
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on a `has_many :through` association from an unsaved model.
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Fix #7661.
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*Ernie Miller*
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* Explain only normal CRUD sql (select / update / insert / delete).
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Fix problem that explains unexplainable sql.
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Closes #7544 #6458.
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*kennyj*
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* Fix `find_in_batches` when primary_key is set other than id.
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You can now use this method with the primary key which is not integer-based.
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Example:
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class Post < ActiveRecord::Base
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self.primary_key = :title
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end
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Post.find_in_batches(start: 'My First Post') do |batch|
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batch.each { |post| post.author.greeting }
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end
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*Toshiyuki Kawanishi*
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* You can now override the generated accessor methods for stored attributes
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and reuse the original behavior with `read_store_attribute` and `write_store_attribute`,
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which are counterparts to `read_attribute` and `write_attribute`.
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*Matt Jones*
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* Accept belongs_to (including polymorphic) association keys in queries.
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The following queries are now equivalent:
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Post.where(author: author)
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Post.where(author_id: author)
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PriceEstimate.where(estimate_of: treasure)
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PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: treasure)
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*Peter Brown*
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* Use native `mysqldump` command instead of `structure_dump` method
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when dumping the database structure to a sql file. Fixes #5547.
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*kennyj*
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* PostgreSQL inet and cidr types are converted to `IPAddr` objects.
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*Dan McClain*
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* PostgreSQL array type support. Any datatype can be used to create an
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array column, with full migration and schema dumper support.
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To declare an array column, use the following syntax:
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create_table :table_with_arrays do |t|
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t.integer :int_array, array: true
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# integer[]
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t.integer :int_array, array: true, length: 2
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# smallint[]
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t.string :string_array, array: true, length: 30
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# char varying(30)[]
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end
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This respects any other migration detail (limits, defaults, etc).
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Active Record will serialize and deserialize the array columns on
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their way to and from the database.
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One thing to note: PostgreSQL does not enforce any limits on the
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number of elements, and any array can be multi-dimensional. Any
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array that is multi-dimensional must be rectangular (each sub array
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must have the same number of elements as its siblings).
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If the `pg_array_parser` gem is available, it will be used when
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parsing PostgreSQL's array representation.
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*Dan McClain*
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* Attribute predicate methods, such as `article.title?`, will now raise
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`ActiveModel::MissingAttributeError` if the attribute being queried for
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truthiness was not read from the database, instead of just returning `false`.
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*Ernie Miller*
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* `ActiveRecord::SchemaDumper` uses Ruby 1.9 style hash, which means that the
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schema.rb file will be generated using this new syntax from now on.
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*Konstantin Shabanov*
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* Map interval with precision to string datatype in PostgreSQL. Fixes #7518.
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*Yves Senn*
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* Fix eagerly loading associations without primary keys. Fixes #4976.
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*Kelley Reynolds*
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* Rails now raise an exception when you're trying to run a migration that has an invalid
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file name. Only lower case letters, numbers, and '_' are allowed in migration's file name.
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Please see #7419 for more details.
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*Jan Bernacki*
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* Fix bug when calling `store_accessor` multiple times.
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Fixes #7532.
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*Matt Jones*
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* Fix store attributes that show the changes incorrectly.
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Fixes #7532.
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*Matt Jones*
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* Fix `ActiveRecord::Relation#pluck` when columns or tables are reserved words.
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*Ian Lesperance*
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* Allow JSON columns to be created in PostgreSQL and properly encoded/decoded.
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to/from database.
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*Dickson S. Guedes*
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* Fix time column type casting for invalid time string values to correctly return `nil`.
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*Adam Meehan*
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* Allow to pass Symbol or Proc into `:limit` option of #accepts_nested_attributes_for.
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*Mikhail Dieterle*
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* ActiveRecord::SessionStore has been extracted from Active Record as `activerecord-session_store`
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gem. Please read the `README.md` file on the gem for the usage.
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*Prem Sichanugrist*
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* Fix `reset_counters` when there are multiple `belongs_to` association with the
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same foreign key and one of them have a counter cache.
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Fixes #5200.
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*Dave Desrochers*
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* `serialized_attributes` and `_attr_readonly` become class method only. Instance reader methods are deprecated.
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*kennyj*
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* Round usec when comparing timestamp attributes in the dirty tracking.
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Fixes #6975.
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*kennyj*
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* Use inversed parent for first and last child of has_many association.
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*Ravil Bayramgalin*
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* Fix Column.microseconds and Column.fast_string_to_date to avoid converting
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timestamp seconds to a float, since it occasionally results in inaccuracies
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with microsecond-precision times. Fixes #7352.
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*Ari Pollak*
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* Raise `ArgumentError` if list of attributes to change is empty in `update_all`.
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*Roman Shatsov*
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* Fix AR#create to return an unsaved record when AR::RecordInvalid is
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raised. Fixes #3217.
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*Dave Yeu*
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* Fixed table name prefix that is generated in engines for namespaced models.
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*Wojciech Wnętrzak*
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* Make sure `:environment` task is executed before `db:schema:load` or `db:structure:load`.
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Fixes #4772.
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*Seamus Abshere*
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* Allow Relation#merge to take a proc.
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This was requested by DHH to allow creating of one's own custom
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association macros.
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For example:
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module Commentable
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def has_many_comments(extra)
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has_many :comments, -> { where(:foo).merge(extra) }
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end
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end
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class Post < ActiveRecord::Base
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extend Commentable
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has_many_comments -> { where(:bar) }
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end
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*Jon Leighton*
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* Add CollectionProxy#scope.
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This can be used to get a Relation from an association.
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Previously we had a #scoped method, but we're deprecating that for
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AR::Base, so it doesn't make sense to have it here.
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This was requested by DHH, to facilitate code like this:
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Project.scope.order('created_at DESC').page(current_page).tagged_with(@tag).limit(5).scoping do
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@topics = @project.topics.scope
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@todolists = @project.todolists.scope
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@attachments = @project.attachments.scope
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@documents = @project.documents.scope
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end
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*Jon Leighton*
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* Add `Relation#load`.
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This method explicitly loads the records and then returns `self`.
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Rather than deciding between "do I want an array or a relation?",
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most people are actually asking themselves "do I want to eager load
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or lazy load?" Therefore, this method provides a way to explicitly
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eager-load without having to switch from a `Relation` to an array.
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Example:
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@posts = Post.where(published: true).load
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*Jon Leighton*
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* `Model.all` now returns an `ActiveRecord::Relation`, rather than an
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array of records. Use `Relation#to_a` if you really want an array.
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In some specific cases, this may cause breakage when upgrading.
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However in most cases the `ActiveRecord::Relation` will just act as a
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lazy-loaded array and there will be no problems.
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Note that calling `Model.all` with options (e.g.
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`Model.all(conditions: '...')` was already deprecated, but it will
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still return an array in order to make the transition easier.
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`Model.scoped` is deprecated in favour of `Model.all`.
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`Relation#all` still returns an array, but is deprecated (since it
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would serve no purpose if we made it return a `Relation`).
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*Jon Leighton*
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* `:finder_sql` and `:counter_sql` options on collection associations
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are deprecated. Please transition to using scopes.
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*Jon Leighton*
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* `:insert_sql` and `:delete_sql` options on `has_and_belongs_to_many`
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associations are deprecated. Please transition to using `has_many
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:through`.
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*Jon Leighton*
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* The migration generator now creates a join table with (commented) indexes every time
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the migration name contains the word `join_table`:
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rails g migration create_join_table_for_artists_and_musics artist_id:index music_id
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*Aleksey Magusev*
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* Add `add_reference` and `remove_reference` schema statements. Aliases, `add_belongs_to`
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and `remove_belongs_to` are acceptable. References are reversible.
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Examples:
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# Create a user_id column
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add_reference(:products, :user)
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# Create a supplier_id, supplier_type columns and appropriate index
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add_reference(:products, :supplier, polymorphic: true, index: true)
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# Remove polymorphic reference
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remove_reference(:products, :supplier, polymorphic: true)
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*Aleksey Magusev*
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* Add `:default` and `:null` options to `column_exists?`.
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column_exists?(:testings, :taggable_id, :integer, null: false)
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column_exists?(:testings, :taggable_type, :string, default: 'Photo')
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*Aleksey Magusev*
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* `ActiveRecord::Relation#inspect` now makes it clear that you are
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dealing with a `Relation` object rather than an array:.
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User.where(age: 30).inspect
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# => <ActiveRecord::Relation [#<User ...>, #<User ...>, ...]>
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User.where(age: 30).to_a.inspect
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# => [#<User ...>, #<User ...>]
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The number of records displayed will be limited to 10.
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*Brian Cardarella, Jon Leighton & Damien Mathieu*
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* Add `collation` and `ctype` support to PostgreSQL. These are available for PostgreSQL 8.4 or later.
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Example:
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development:
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adapter: postgresql
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host: localhost
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database: rails_development
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username: foo
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password: bar
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encoding: UTF8
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collation: ja_JP.UTF8
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ctype: ja_JP.UTF8
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*kennyj*
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* Changed validates_presence_of on an association so that children objects
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do not validate as being present if they are marked for destruction. This
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prevents you from saving the parent successfully and thus putting the parent
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in an invalid state.
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*Nick Monje & Brent Wheeldon*
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* `FinderMethods#exists?` now returns `false` with the `false` argument.
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*Egor Lynko*
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* Added support for specifying the precision of a timestamp in the postgresql
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adapter. So, instead of having to incorrectly specify the precision using the
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`:limit` option, you may use `:precision`, as intended. For example, in a migration:
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def change
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create_table :foobars do |t|
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t.timestamps :precision => 0
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end
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end
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*Tony Schneider*
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* Allow `ActiveRecord::Relation#pluck` to accept multiple columns. Returns an
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array of arrays containing the typecasted values:
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Person.pluck(:id, :name)
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# SELECT people.id, people.name FROM people
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# [[1, 'David'], [2, 'Jeremy'], [3, 'Jose']]
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*Jeroen van Ingen & Carlos Antonio da Silva*
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* Improve the derivation of HABTM join table name to take account of nesting.
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It now takes the table names of the two models, sorts them lexically and
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then joins them, stripping any common prefix from the second table name.
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Some examples:
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Top level models (Category <=> Product)
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Old: categories_products
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New: categories_products
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Top level models with a global table_name_prefix (Category <=> Product)
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Old: site_categories_products
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New: site_categories_products
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Nested models in a module without a table_name_prefix method (Admin::Category <=> Admin::Product)
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Old: categories_products
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New: categories_products
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Nested models in a module with a table_name_prefix method (Admin::Category <=> Admin::Product)
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Old: categories_products
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New: admin_categories_products
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Nested models in a parent model (Catalog::Category <=> Catalog::Product)
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Old: categories_products
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New: catalog_categories_products
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Nested models in different parent models (Catalog::Category <=> Content::Page)
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Old: categories_pages
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New: catalog_categories_content_pages
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*Andrew White*
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* Move HABTM validity checks to `ActiveRecord::Reflection`. One side effect of
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this is to move when the exceptions are raised from the point of declaration
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to when the association is built. This is consistant with other association
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validity checks.
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*Andrew White*
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* Added `stored_attributes` hash which contains the attributes stored using
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`ActiveRecord::Store`. This allows you to retrieve the list of attributes
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you've defined.
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class User < ActiveRecord::Base
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store :settings, accessors: [:color, :homepage]
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end
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User.stored_attributes[:settings] # [:color, :homepage]
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*Joost Baaij & Carlos Antonio da Silva*
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* PostgreSQL default log level is now 'warning', to bypass the noisy notice
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messages. You can change the log level using the `min_messages` option
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available in your config/database.yml.
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*kennyj*
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* Add uuid datatype support to PostgreSQL adapter.
|
||
|
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*Konstantin Shabanov*
|
||
|
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* Added `ActiveRecord::Migration.check_pending!` that raises an error if
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migrations are pending.
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||
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*Richard Schneeman*
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||
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* Added `#destroy!` which acts like `#destroy` but will raise an
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`ActiveRecord::RecordNotDestroyed` exception instead of returning `false`.
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*Marc-André Lafortune*
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* Allow blocks for `count` with `ActiveRecord::Relation`, to work similar as
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`Array#count`:
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Person.where("age > 26").count { |person| person.gender == 'female' }
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*Chris Finne & Carlos Antonio da Silva*
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* Added support to `CollectionAssociation#delete` for passing `fixnum`
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or `string` values as record ids. This finds the records responding
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to the `id` and executes delete on them.
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class Person < ActiveRecord::Base
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has_many :pets
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end
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person.pets.delete("1") # => [#<Pet id: 1>]
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person.pets.delete(2, 3) # => [#<Pet id: 2>, #<Pet id: 3>]
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*Francesco Rodriguez*
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||
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* Deprecated most of the 'dynamic finder' methods. All dynamic methods
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except for `find_by_...` and `find_by_...!` are deprecated. Here's
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how you can rewrite the code:
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* `find_all_by_...` can be rewritten using `where(...)`
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* `find_last_by_...` can be rewritten using `where(...).last`
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* `scoped_by_...` can be rewritten using `where(...)`
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* `find_or_initialize_by_...` can be rewritten using
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`where(...).first_or_initialize`
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* `find_or_create_by_...` can be rewritten using
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`where(...).first_or_create`
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* `find_or_create_by_...!` can be rewritten using
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`where(...).first_or_create!`
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The implementation of the deprecated dynamic finders has been moved
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to the `activerecord-deprecated_finders` gem. See below for details.
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*Jon Leighton*
|
||
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||
* Deprecated the old-style hash based finder API. This means that
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methods which previously accepted "finder options" no longer do. For
|
||
example this:
|
||
|
||
Post.find(:all, conditions: { comments_count: 10 }, limit: 5)
|
||
|
||
Should be rewritten in the new style which has existed since Rails 3:
|
||
|
||
Post.where(comments_count: 10).limit(5)
|
||
|
||
Note that as an interim step, it is possible to rewrite the above as:
|
||
|
||
Post.all.merge(where: { comments_count: 10 }, limit: 5)
|
||
|
||
This could save you a lot of work if there is a lot of old-style
|
||
finder usage in your application.
|
||
|
||
`Relation#merge` now accepts a hash of
|
||
options, but they must be identical to the names of the equivalent
|
||
finder method. These are mostly identical to the old-style finder
|
||
option names, except in the following cases:
|
||
|
||
* `:conditions` becomes `:where`.
|
||
* `:include` becomes `:includes`.
|
||
* `:extend` becomes `:extending`.
|
||
|
||
The code to implement the deprecated features has been moved out to
|
||
the `activerecord-deprecated_finders` gem. This gem is a dependency
|
||
of Active Record in Rails 4.0. It will no longer be a dependency
|
||
from Rails 4.1, but if your app relies on the deprecated features
|
||
then you can add it to your own Gemfile. It will be maintained by
|
||
the Rails core team until Rails 5.0 is released.
|
||
|
||
*Jon Leighton*
|
||
|
||
* It's not possible anymore to destroy a model marked as read only.
|
||
|
||
*Johannes Barre*
|
||
|
||
* Added ability to ActiveRecord::Relation#from to accept other ActiveRecord::Relation objects.
|
||
|
||
Record.from(subquery)
|
||
Record.from(subquery, :a)
|
||
|
||
*Radoslav Stankov*
|
||
|
||
* Added custom coders support for ActiveRecord::Store. Now you can set
|
||
your custom coder like this:
|
||
|
||
store :settings, accessors: [ :color, :homepage ], coder: JSON
|
||
|
||
*Andrey Voronkov*
|
||
|
||
* `mysql` and `mysql2` connections will set `SQL_MODE=STRICT_ALL_TABLES` by
|
||
default to avoid silent data loss. This can be disabled by specifying
|
||
`strict: false` in your `database.yml`.
|
||
|
||
*Michael Pearson*
|
||
|
||
* Added default order to `first` to assure consistent results among
|
||
diferent database engines. Introduced `take` as a replacement to
|
||
the old behavior of `first`.
|
||
|
||
*Marcelo Silveira*
|
||
|
||
* Added an `:index` option to automatically create indexes for references
|
||
and belongs_to statements in migrations.
|
||
|
||
The `references` and `belongs_to` methods now support an `index`
|
||
option that receives either a boolean value or an options hash
|
||
that is identical to options available to the add_index method:
|
||
|
||
create_table :messages do |t|
|
||
t.references :person, index: true
|
||
end
|
||
|
||
Is the same as:
|
||
|
||
create_table :messages do |t|
|
||
t.references :person
|
||
end
|
||
add_index :messages, :person_id
|
||
|
||
Generators have also been updated to use the new syntax.
|
||
|
||
*Joshua Wood*
|
||
|
||
* Added bang methods for mutating `ActiveRecord::Relation` objects.
|
||
For example, while `foo.where(:bar)` will return a new object
|
||
leaving `foo` unchanged, `foo.where!(:bar)` will mutate the foo
|
||
object
|
||
|
||
*Jon Leighton*
|
||
|
||
* Added `#find_by` and `#find_by!` to mirror the functionality
|
||
provided by dynamic finders in a way that allows dynamic input more
|
||
easily:
|
||
|
||
Post.find_by name: 'Spartacus', rating: 4
|
||
Post.find_by "published_at < ?", 2.weeks.ago
|
||
Post.find_by! name: 'Spartacus'
|
||
|
||
*Jon Leighton*
|
||
|
||
* Added ActiveRecord::Base#slice to return a hash of the given methods with
|
||
their names as keys and returned values as values.
|
||
|
||
*Guillermo Iguaran*
|
||
|
||
* Deprecate eager-evaluated scopes.
|
||
|
||
Don't use this:
|
||
|
||
scope :red, where(color: 'red')
|
||
default_scope where(color: 'red')
|
||
|
||
Use this:
|
||
|
||
scope :red, -> { where(color: 'red') }
|
||
default_scope { where(color: 'red') }
|
||
|
||
The former has numerous issues. It is a common newbie gotcha to do
|
||
the following:
|
||
|
||
scope :recent, where(published_at: Time.now - 2.weeks)
|
||
|
||
Or a more subtle variant:
|
||
|
||
scope :recent, -> { where(published_at: Time.now - 2.weeks) }
|
||
scope :recent_red, recent.where(color: 'red')
|
||
|
||
Eager scopes are also very complex to implement within Active
|
||
Record, and there are still bugs. For example, the following does
|
||
not do what you expect:
|
||
|
||
scope :remove_conditions, except(:where)
|
||
where(...).remove_conditions # => still has conditions
|
||
|
||
*Jon Leighton*
|
||
|
||
* Remove IdentityMap
|
||
|
||
IdentityMap has never graduated to be an "enabled-by-default" feature, due
|
||
to some inconsistencies with associations, as described in this commit:
|
||
|
||
https://github.com/rails/rails/commit/302c912bf6bcd0fa200d964ec2dc4a44abe328a6
|
||
|
||
Hence the removal from the codebase, until such issues are fixed.
|
||
|
||
*Carlos Antonio da Silva*
|
||
|
||
* Added the schema cache dump feature.
|
||
|
||
`Schema cache dump` feature was implemetend. This feature can dump/load internal state of `SchemaCache` instance
|
||
because we want to boot rails more quickly when we have many models.
|
||
|
||
Usage notes:
|
||
|
||
1) execute rake task.
|
||
RAILS_ENV=production bundle exec rake db:schema:cache:dump
|
||
=> generate db/schema_cache.dump
|
||
|
||
2) add config.active_record.use_schema_cache_dump = true in config/production.rb. BTW, true is default.
|
||
|
||
3) boot rails.
|
||
RAILS_ENV=production bundle exec rails server
|
||
=> use db/schema_cache.dump
|
||
|
||
4) If you remove clear dumped cache, execute rake task.
|
||
RAILS_ENV=production bundle exec rake db:schema:cache:clear
|
||
=> remove db/schema_cache.dump
|
||
|
||
*kennyj*
|
||
|
||
* Added support for partial indices to PostgreSQL adapter.
|
||
|
||
The `add_index` method now supports a `where` option that receives a
|
||
string with the partial index criteria.
|
||
|
||
add_index(:accounts, :code, where: 'active')
|
||
|
||
Generates
|
||
|
||
CREATE INDEX index_accounts_on_code ON accounts(code) WHERE active
|
||
|
||
*Marcelo Silveira*
|
||
|
||
* Implemented ActiveRecord::Relation#none method.
|
||
|
||
The `none` method returns a chainable relation with zero records
|
||
(an instance of the NullRelation class).
|
||
|
||
Any subsequent condition chained to the returned relation will continue
|
||
generating an empty relation and will not fire any query to the database.
|
||
|
||
*Juanjo Bazán*
|
||
|
||
* Added the `ActiveRecord::NullRelation` class implementing the null
|
||
object pattern for the Relation class.
|
||
|
||
*Juanjo Bazán*
|
||
|
||
* Added new `dependent: :restrict_with_error` option. This will add
|
||
an error to the model, rather than raising an exception.
|
||
|
||
The `:restrict` option is renamed to `:restrict_with_exception` to
|
||
make this distinction explicit.
|
||
|
||
*Manoj Kumar & Jon Leighton*
|
||
|
||
* Added `create_join_table` migration helper to create HABTM join tables.
|
||
|
||
create_join_table :products, :categories
|
||
# =>
|
||
# create_table :categories_products, id: false do |td|
|
||
# td.integer :product_id, null: false
|
||
# td.integer :category_id, null: false
|
||
# end
|
||
|
||
*Rafael Mendonça França*
|
||
|
||
* The primary key is always initialized in the @attributes hash to `nil` (unless
|
||
another value has been specified).
|
||
|
||
*Aaron Paterson*
|
||
|
||
* In previous releases, the following would generate a single query with
|
||
an `OUTER JOIN comments`, rather than two separate queries:
|
||
|
||
Post.includes(:comments)
|
||
.where("comments.name = 'foo'")
|
||
|
||
This behaviour relies on matching SQL string, which is an inherently
|
||
flawed idea unless we write an SQL parser, which we do not wish to
|
||
do.
|
||
|
||
Therefore, it is now deprecated.
|
||
|
||
To avoid deprecation warnings and for future compatibility, you must
|
||
explicitly state which tables you reference, when using SQL snippets:
|
||
|
||
Post.includes(:comments)
|
||
.where("comments.name = 'foo'")
|
||
.references(:comments)
|
||
|
||
Note that you do not need to explicitly specify references in the
|
||
following cases, as they can be automatically inferred:
|
||
|
||
Post.where(comments: { name: 'foo' })
|
||
Post.where('comments.name' => 'foo')
|
||
Post.order('comments.name')
|
||
|
||
You also do not need to worry about this unless you are doing eager
|
||
loading. Basically, don't worry unless you see a deprecation warning
|
||
or (in future releases) an SQL error due to a missing JOIN.
|
||
|
||
*Jon Leighton*
|
||
|
||
* Support for the `schema_info` table has been dropped. Please
|
||
switch to `schema_migrations`.
|
||
|
||
*Aaron Patterson*
|
||
|
||
* Connections *must* be closed at the end of a thread. If not, your
|
||
connection pool can fill and an exception will be raised.
|
||
|
||
*Aaron Patterson*
|
||
|
||
* Added the `ActiveRecord::Model` module which can be included in a
|
||
class as an alternative to inheriting from `ActiveRecord::Base`:
|
||
|
||
class Post
|
||
include ActiveRecord::Model
|
||
end
|
||
|
||
Please note:
|
||
|
||
* Up until now it has been safe to assume that all AR models are
|
||
descendants of `ActiveRecord::Base`. This is no longer a safe
|
||
assumption, but it may transpire that there are areas of the
|
||
code which still make this assumption. So there may be
|
||
'teething difficulties' with this feature. (But please do try it
|
||
and report bugs.)
|
||
|
||
* Plugins & libraries etc that add methods to `ActiveRecord::Base`
|
||
will not be compatible with `ActiveRecord::Model`. Those libraries
|
||
should add to `ActiveRecord::Model` instead (which is included in
|
||
`Base`), or better still, avoid monkey-patching AR and instead
|
||
provide a module that users can include where they need it.
|
||
|
||
* To minimise the risk of conflicts with other code, it is
|
||
advisable to include `ActiveRecord::Model` early in your class
|
||
definition.
|
||
|
||
*Jon Leighton*
|
||
|
||
* PostgreSQL hstore records can be created.
|
||
|
||
*Aaron Patterson*
|
||
|
||
* PostgreSQL hstore types are automatically deserialized from the database.
|
||
|
||
*Aaron Patterson*
|
||
|
||
Please check [3-2-stable](https://github.com/rails/rails/blob/3-2-stable/activerecord/CHANGELOG.md) for previous changes.
|