These queries don't seem to work without the includes clause. [ci skip]
37 KiB
Rails 4.0.0 (unreleased)
-
Allow
Relation#where
with no arguments to be chained with newnot
query method.Example:
Developer.where.not(name: 'Aaron')
Akira Matsuda
-
Unscope
update_column(s)
query to ignore default scope.When applying
default_scope
to a class with a where clause, usingupdate_column(s)
could generate a query that would not properly update the record due to the where clause from thedefault_scope
being applied to the update query.class User < ActiveRecord::Base default_scope where(active: true) end user = User.first user.active = false user.save! user.update_column(:active, true) # => false
In this situation we want to skip the default_scope clause and just update the record based on the primary key. With this change:
user.update_column(:active, true) # => true
Fixes #8436.
Carlos Antonio da Silva
-
SQLite adapter no longer corrupts binary data if the data contains
%00
.Chris Feist
-
Add migration history to
schema.rb
dump. Loadingschema.rb
with full migration history restores the exact list of migrations that created that schema (including names and fingerprints). This avoids possible mistakes caused by assuming all migrations with a lower version have been run when loadingschema.rb
. Oldschema.rb
files without migration history but with the:version
setting still work as before.Josh Susser
-
Add metadata columns to
schema_migrations
table. New columns are:migrated_at
: timestampfingerprint
: md5 hash of migration sourcename
: filename minus version and extension
Josh Susser
-
Fix performance problem with
primary_key
method in PostgreSQL adapter when having many schemas. Usespg_constraint
table instead ofpg_depend
table which has many records in general. Fix #8414kennyj
-
Do not instantiate intermediate Active Record objects when eager loading. These records caused
after_find
to run more than expected. Fix #3313Yves Senn
-
Add STI support to init and building associations. Allows you to do
BaseClass.new(:type => "SubClass")
as well asparent.children.build(:type => "SubClass")
orparent.build_child
to initialize an STI subclass. Ensures that the class name is a valid class and that it is in the ancestors of the super class that the association is expecting.Jason Rush
-
Observers was extracted from Active Record as
rails-observers
gem.Rafael Mendonça França
-
Ensure that associations take a symbol argument. Steve Klabnik
-
Fix dirty attribute checks for
TimeZoneConversion
with nil and blank datetime attributes. Setting a nil datetime to a blank string should not result in a change being flagged. Fix #8310Alisdair McDiarmid
-
Prevent mass assignment to the type column of polymorphic associations when using
build
Fix #8265Yves Senn
-
Deprecate calling
Relation#sum
with a block. To perform a calculation over the array result of the relation, useto_a.sum(&block)
.Carlos Antonio da Silva
-
Fix postgresql adapter to handle BC timestamps correctly
HistoryEvent.create!(:name => "something", :occured_at => Date.new(0) - 5.years)
Bogdan Gusiev
-
When running migrations on Postgresql, the
:limit
option forbinary
andtext
columns is silently dropped. Previously, these migrations caused sql exceptions, because Postgresql doesn't support limits on these types.Victor Costan
-
Don't change STI type when calling
ActiveRecord::Base#becomes
. AddActiveRecord::Base#becomes!
with the previous behavior.See #3023 for more information.
Thomas Hollstegge
-
rename_index
can be used inside achange_table
block.change_table :accounts do |t| t.rename_index :user_id, :account_id end
Jarek Radosz
-
#pluck
can be used on a relation withselect
clause. Fix #7551Example:
Topic.select([:approved, :id]).order(:id).pluck(:id)
Yves Senn
-
Do not create useless database transaction when building
has_one
association.Example:
User.has_one :profile User.new.build_profile
Bogdan Gusiev
-
:counter_cache
option forhas_many
associations to support custom named counter caches. Fix #7993Yves Senn
-
Deprecate the possibility to pass a string as third argument of
add_index
. Passunique: true
instead.add_index(:users, :organization_id, unique: true)
Rafael Mendonça França
-
Raise an
ArgumentError
when passing an invalid option toadd_index
.Rafael Mendonça França
-
Fix
find_in_batches
crashing when IDs are strings and start option is not specified.Alexis Bernard
-
AR::Base#attributes_before_type_cast
now returns unserialized values for serialized attributes.Nikita Afanasenko
-
Use query cache/uncache when using
DATABASE_URL
. Fix #6951.kennyj
-
Added
#none!
method for mutatingActiveRecord::Relation
objects to a NullRelation. It acts like#none
but modifies relation in place.Juanjo Bazán
-
Fix bug where
update_columns
andupdate_column
would not let you update the primary key column.Henrik Nyh
-
The
create_table
method raises anArgumentError
when the primary key column is redefined. Fix #6378Yves Senn
-
ActiveRecord::AttributeMethods#[]
raisesActiveModel::MissingAttributeError
error if the given attribute is missing. Fixes #5433.class Person < ActiveRecord::Base belongs_to :company end # Before: person = Person.select('id').first person[:name] # => nil person.name # => ActiveModel::MissingAttributeError: missing_attribute: name person[:company_id] # => nil person.company # => nil # After: person = Person.select('id').first person[:name] # => ActiveModel::MissingAttributeError: missing_attribute: name person.name # => ActiveModel::MissingAttributeError: missing_attribute: name person[:company_id] # => ActiveModel::MissingAttributeError: missing_attribute: company_id person.company # => ActiveModel::MissingAttributeError: missing_attribute: company_id
Francesco Rodriguez
-
Small binary fields use the
VARBINARY
MySQL type, instead ofTINYBLOB
.Victor Costan
-
Decode URI encoded attributes on database connection URLs.
Shawn Veader
-
Add
find_or_create_by
,find_or_create_by!
andfind_or_initialize_by
methods toRelation
.These are similar to the
first_or_create
family of methods, but the behaviour when a record is created is slightly different:User.where(first_name: 'Penélope').first_or_create
will execute:
User.where(first_name: 'Penélope').create
Causing all the
create
callbacks to execute within the context of the scope. This could affect queries that occur within callbacks.User.find_or_create_by(first_name: 'Penélope')
will execute:
User.create(first_name: 'Penélope')
Which obviously does not affect the scoping of queries within callbacks.
The
find_or_create_by
version also reads better, frankly.If you need to add extra attributes during create, you can do one of:
User.create_with(active: true).find_or_create_by(first_name: 'Jon') User.find_or_create_by(first_name: 'Jon') { |u| u.active = true }
The
first_or_create
family of methods have been nodoc'ed in favour of this API. They may be deprecated in the future but their implementation is very small and it's probably not worth putting users through lots of annoying deprecation warnings.Jon Leighton
-
Fix bug with presence validation of associations. Would incorrectly add duplicated errors when the association was blank. Bug introduced in
1fab518c6a
.Scott Willson
-
Fix bug where sum(expression) returns string '0' for no matching records. Fixes #7439
Tim Macfarlane
-
PostgreSQL adapter correctly fetches default values when using multiple schemas and domains in a db. Fixes #7914
Arturo Pie
-
Learn ActiveRecord::QueryMethods#order work with hash arguments
When symbol or hash passed we convert it to Arel::Nodes::Ordering. If we pass invalid direction(like name: :DeSc) ActiveRecord::QueryMethods#order will raise an exception
User.order(:name, email: :desc) # SELECT "users".* FROM "users" ORDER BY "users"."name" ASC, "users"."email" DESC
Tima Maslyuchenko
-
Rename
ActiveRecord::Fixtures
class toActiveRecord::FixtureSet
. Instances of this class normally hold a collection of fixtures (records) loaded either from a single YAML file, or from a file and a folder with the same name. This change make the class name singular and makes the class easier to distinguish from the modules likeActiveRecord::TestFixtures
, which operates on multiple fixture sets, orDelegatingFixtures
,::Fixtures
, etc., and from the classActiveRecord::Fixture
, which corresponds to a single fixture.Alexey Muranov
-
The postgres adapter now supports tables with capital letters. Fix #5920
Yves Senn
-
CollectionAssociation#count
returns0
without querying if the parent record is not persisted.Before:
person.pets.count # SELECT COUNT(*) FROM "pets" WHERE "pets"."person_id" IS NULL # => 0
After:
person.pets.count # fires without sql query # => 0
Francesco Rodriguez
-
Fix
reset_counters
crashing onhas_many :through
associations. Fix #7822.lulalala
-
Support for partial inserts.
When inserting new records, only the fields which have been changed from the defaults will actually be included in the INSERT statement. The other fields will be populated by the database.
This is more efficient, and also means that it will be safe to remove database columns without getting subsequent errors in running app processes (so long as the code in those processes doesn't contain any references to the removed column).
The
partial_updates
configuration option is now renamed topartial_writes
to reflect the fact that it now impacts both inserts and updates.Jon Leighton
-
Allow before and after validations to take an array of lifecycle events
John Foley
-
Support for specifying transaction isolation level
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.
Jon Leighton
-
ActiveModel::ForbiddenAttributesProtection
is included by default in Active Record models. Check the docs ofActiveModel::ForbiddenAttributesProtection
for more details.Guillermo Iguaran
-
Remove integration between Active Record and
ActiveModel::MassAssignmentSecurity
,protected_attributes
gem should be added to useattr_accessible
/attr_protected
. Mass assignment options has been removed from all the AR methods that used it (ex.AR::Base.new
,AR::Base.create
,AR::Base#update_attributes
, etc).Guillermo Iguaran
-
Fix the return of querying with an empty hash. Fix #6971.
User.where(token: {})
Before:
#=> SELECT * FROM users;
After:
#=> SELECT * FROM users WHERE 1 = 2;
Damien Mathieu
-
Fix creation of through association models when using
collection=[]
on ahas_many :through
association from an unsaved model. Fix #7661.Ernie Miller
-
Explain only normal CRUD sql (select / update / insert / delete). Fix problem that explains unexplainable sql. Closes #7544 #6458.
kennyj
-
You can now override the generated accessor methods for stored attributes and reuse the original behavior with
read_store_attribute
andwrite_store_attribute
, which are counterparts toread_attribute
andwrite_attribute
.Matt Jones
-
Accept belongs_to (including polymorphic) association keys in queries.
The following queries are now equivalent:
Post.where(author: author) Post.where(author_id: author) PriceEstimate.where(estimate_of: treasure) PriceEstimate.where(estimate_of_type: 'Treasure', estimate_of_id: treasure)
Peter Brown
-
Use native
mysqldump
command instead ofstructure_dump
method when dumping the database structure to a sql file. Fixes #5547.kennyj
-
PostgreSQL inet and cidr types are converted to
IPAddr
objects.Dan McClain
-
PostgreSQL array type support. Any datatype can be used to create an array column, with full migration and schema dumper support.
To declare an array column, use the following syntax:
create_table :table_with_arrays do |t| t.integer :int_array, array: true # integer[] t.integer :int_array, array: true, length: 2 # smallint[] t.string :string_array, array: true, length: 30 # char varying(30)[] end
This respects any other migration detail (limits, defaults, etc). Active Record will serialize and deserialize the array columns on their way to and from the database.
One thing to note: PostgreSQL does not enforce any limits on the number of elements, and any array can be multi-dimensional. Any array that is multi-dimensional must be rectangular (each sub array must have the same number of elements as its siblings).
If the
pg_array_parser
gem is available, it will be used when parsing PostgreSQL's array representation.Dan McClain
-
Attribute predicate methods, such as
article.title?
, will now raiseActiveModel::MissingAttributeError
if the attribute being queried for truthiness was not read from the database, instead of just returningfalse
.Ernie Miller
-
ActiveRecord::SchemaDumper
uses Ruby 1.9 style hash, which means that the schema.rb file will be generated using this new syntax from now on.Konstantin Shabanov
-
Map interval with precision to string datatype in PostgreSQL. Fixes #7518.
Yves Senn
-
Fix eagerly loading associations without primary keys. Fixes #4976.
Kelley Reynolds
-
Rails now raise an exception when you're trying to run a migration that has an invalid file name. Only lower case letters, numbers, and '_' are allowed in migration's file name. Please see #7419 for more details.
Jan Bernacki
-
Fix bug when calling
store_accessor
multiple times. Fixes #7532.Matt Jones
-
Fix store attributes that show the changes incorrectly. Fixes #7532.
Matt Jones
-
Fix
ActiveRecord::Relation#pluck
when columns or tables are reserved words.Ian Lesperance
-
Allow JSON columns to be created in PostgreSQL and properly encoded/decoded. to/from database.
Dickson S. Guedes
-
Fix time column type casting for invalid time string values to correctly return
nil
.Adam Meehan
-
Allow to pass Symbol or Proc into
:limit
option of #accepts_nested_attributes_for.Mikhail Dieterle
-
ActiveRecord::SessionStore has been extracted from Active Record as
activerecord-session_store
gem. Please read theREADME.md
file on the gem for the usage.Prem Sichanugrist
-
Fix
reset_counters
when there are multiplebelongs_to
association with the same foreign key and one of them have a counter cache. Fixes #5200.Dave Desrochers
-
serialized_attributes
and_attr_readonly
become class method only. Instance reader methods are deprecated.kennyj
-
Round usec when comparing timestamp attributes in the dirty tracking. Fixes #6975.
kennyj
-
Use inversed parent for first and last child of
has_many
association.Ravil Bayramgalin
-
Fix
Column.microseconds
andColumn.fast_string_to_time
to avoid converting timestamp seconds to a float, since it occasionally results in inaccuracies with microsecond-precision times. Fixes #7352.Ari Pollak
-
Fix AR#dup to nullify the validation errors in the dup'ed object. Previously the original and the dup'ed object shared the same errors.
Christian Seiler
-
Raise
ArgumentError
if list of attributes to change is empty inupdate_all
.Roman Shatsov
-
Fix AR#create to return an unsaved record when AR::RecordInvalid is raised. Fixes #3217.
Dave Yeu
-
Fixed table name prefix that is generated in engines for namespaced models.
Wojciech Wnętrzak
-
Make sure
:environment
task is executed beforedb:schema:load
ordb:structure:load
. Fixes #4772.Seamus Abshere
-
Allow Relation#merge to take a proc.
This was requested by DHH to allow creating of one's own custom association macros.
For example:
module Commentable def has_many_comments(extra) has_many :comments, -> { where(:foo).merge(extra) } end end class Post < ActiveRecord::Base extend Commentable has_many_comments -> { where(:bar) } end
Jon Leighton
-
Add CollectionProxy#scope.
This can be used to get a Relation from an association.
Previously we had a #scoped method, but we're deprecating that for AR::Base, so it doesn't make sense to have it here.
This was requested by DHH, to facilitate code like this:
Project.scope.order('created_at DESC').page(current_page).tagged_with(@tag).limit(5).scoping do @topics = @project.topics.scope @todolists = @project.todolists.scope @attachments = @project.attachments.scope @documents = @project.documents.scope end
Jon Leighton
-
Add
Relation#load
.This method explicitly loads the records and then returns
self
.Rather than deciding between "do I want an array or a relation?", most people are actually asking themselves "do I want to eager load or lazy load?" Therefore, this method provides a way to explicitly eager-load without having to switch from a
Relation
to an array.Example:
@posts = Post.where(published: true).load
Jon Leighton
-
Relation#order
: make new order prepend old one.User.order("name asc").order("created_at desc") # SELECT * FROM users ORDER BY created_at desc, name asc
This also affects order defined in
default_scope
or any kind of associations.Bogdan Gusiev
-
Model.all
now returns anActiveRecord::Relation
, rather than an array of records. UseRelation#to_a
if you really want an array.In some specific cases, this may cause breakage when upgrading. However in most cases the
ActiveRecord::Relation
will just act as a lazy-loaded array and there will be no problems.Note that calling
Model.all
with options (e.g.Model.all(conditions: '...')
was already deprecated, but it will still return an array in order to make the transition easier.Model.scoped
is deprecated in favour ofModel.all
.Relation#all
still returns an array, but is deprecated (since it would serve no purpose if we made it return aRelation
).Jon Leighton
-
:finder_sql
and:counter_sql
options on collection associations are deprecated. Please transition to using scopes.Jon Leighton
-
:insert_sql
and:delete_sql
options onhas_and_belongs_to_many
associations are deprecated. Please transition to usinghas_many :through
.Jon Leighton
-
Added
#update_columns
method which updates the attributes from the passed-in hash without calling save, hence skipping validations and callbacks.ActiveRecordError
will be raised when called on new objects or when at least one of the attributes is marked as read only.post.attributes # => {"id"=>2, "title"=>"My title", "body"=>"My content", "author"=>"Peter"} post.update_columns(title: 'New title', author: 'Sebastian') # => true post.attributes # => {"id"=>2, "title"=>"New title", "body"=>"My content", "author"=>"Sebastian"}
Sebastian Martinez + Rafael Mendonça França
-
The migration generator now creates a join table with (commented) indexes every time the migration name contains the word
join_table
:rails g migration create_join_table_for_artists_and_musics artist_id:index music_id
Aleksey Magusev
-
Add
add_reference
andremove_reference
schema statements. Aliases,add_belongs_to
andremove_belongs_to
are acceptable. References are reversible.Examples:
# Create a user_id column add_reference(:products, :user) # Create a supplier_id, supplier_type columns and appropriate index add_reference(:products, :supplier, polymorphic: true, index: true) # Remove polymorphic reference remove_reference(:products, :supplier, polymorphic: true)
Aleksey Magusev
-
Add
:default
and:null
options tocolumn_exists?
.column_exists?(:testings, :taggable_id, :integer, null: false) column_exists?(:testings, :taggable_type, :string, default: 'Photo')
Aleksey Magusev
-
ActiveRecord::Relation#inspect
now makes it clear that you are dealing with aRelation
object rather than an array:.User.where(age: 30).inspect # => <ActiveRecord::Relation [#<User ...>, #<User ...>, ...]> User.where(age: 30).to_a.inspect # => [#<User ...>, #<User ...>]
The number of records displayed will be limited to 10.
Brian Cardarella, Jon Leighton & Damien Mathieu
-
Add
collation
andctype
support to PostgreSQL. These are available for PostgreSQL 8.4 or later. Example:development: adapter: postgresql host: localhost database: rails_development username: foo password: bar encoding: UTF8 collation: ja_JP.UTF8 ctype: ja_JP.UTF8
kennyj
-
Changed validates_presence_of on an association so that children objects do not validate as being present if they are marked for destruction. This prevents you from saving the parent successfully and thus putting the parent in an invalid state.
Nick Monje & Brent Wheeldon
-
FinderMethods#exists?
now returnsfalse
with thefalse
argument.Egor Lynko
-
Added support for specifying the precision of a timestamp in the postgresql adapter. So, instead of having to incorrectly specify the precision using the
:limit
option, you may use:precision
, as intended. For example, in a migration:def change create_table :foobars do |t| t.timestamps :precision => 0 end end
Tony Schneider
-
Allow
ActiveRecord::Relation#pluck
to accept multiple columns. Returns an array of arrays containing the typecasted values:Person.pluck(:id, :name) # SELECT people.id, people.name FROM people # [[1, 'David'], [2, 'Jeremy'], [3, 'Jose']]
Jeroen van Ingen & Carlos Antonio da Silva
-
Improve the derivation of HABTM join table name to take account of nesting. It now takes the table names of the two models, sorts them lexically and then joins them, stripping any common prefix from the second table name.
Some examples:
Top level models (Category <=> Product) Old: categories_products New: categories_products Top level models with a global table_name_prefix (Category <=> Product) Old: site_categories_products New: site_categories_products Nested models in a module without a table_name_prefix method (Admin::Category <=> Admin::Product) Old: categories_products New: categories_products Nested models in a module with a table_name_prefix method (Admin::Category <=> Admin::Product) Old: categories_products New: admin_categories_products Nested models in a parent model (Catalog::Category <=> Catalog::Product) Old: categories_products New: catalog_categories_products Nested models in different parent models (Catalog::Category <=> Content::Page) Old: categories_pages New: catalog_categories_content_pages
Andrew White
-
Move HABTM validity checks to
ActiveRecord::Reflection
. One side effect of this is to move when the exceptions are raised from the point of declaration to when the association is built. This is consistant with other association validity checks.Andrew White
-
Added
stored_attributes
hash which contains the attributes stored usingActiveRecord::Store
. This allows you to retrieve the list of attributes you've defined.class User < ActiveRecord::Base store :settings, accessors: [:color, :homepage] end
User.stored_attributes[:settings] # [:color, :homepage]
Joost Baaij & Carlos Antonio da Silva
-
PostgreSQL default log level is now 'warning', to bypass the noisy notice messages. You can change the log level using the
min_messages
option available in your config/database.yml.kennyj
-
Add uuid datatype support to PostgreSQL adapter.
Konstantin Shabanov
-
Added
ActiveRecord::Migration.check_pending!
that raises an error if migrations are pending.Richard Schneeman
-
Added
#destroy!
which acts like#destroy
but will raise anActiveRecord::RecordNotDestroyed
exception instead of returningfalse
.Marc-André Lafortune
-
Added support to
CollectionAssociation#delete
for passingfixnum
orstring
values as record ids. This finds the records responding to theid
and executes delete on them.class Person < ActiveRecord::Base has_many :pets end person.pets.delete("1") # => [#<Pet id: 1>] person.pets.delete(2, 3) # => [#<Pet id: 2>, #<Pet id: 3>]
Francesco Rodriguez
-
Deprecated most of the 'dynamic finder' methods. All dynamic methods except for
find_by_...
andfind_by_...!
are deprecated. Here's how you can rewrite the code:find_all_by_...
can be rewritten usingwhere(...)
find_last_by_...
can be rewritten usingwhere(...).last
scoped_by_...
can be rewritten usingwhere(...)
find_or_initialize_by_...
can be rewritten usingwhere(...).first_or_initialize
find_or_create_by_...
can be rewritten usingfind_or_create_by(...)
or where(...).first_or_create`find_or_create_by_...!
can be rewritten usingfind_or_create_by!(...) or
where(...).first_or_create!`
The implementation of the deprecated dynamic finders has been moved to the
activerecord-deprecated_finders
gem. See below for details.Jon Leighton
-
Deprecated the old-style hash based finder API. This means that 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
andmysql2
connections will setSQL_MODE=STRICT_ALL_TABLES
by default to avoid silent data loss. This can be disabled by specifyingstrict: false
in yourdatabase.yml
.Michael Pearson
-
Added default order to
first
to assure consistent results among different database engines. Introducedtake
as a replacement to the old behavior offirst
.Marcelo Silveira
-
Added an
:index
option to automatically create indexes for references and belongs_to statements in migrations.The
references
andbelongs_to
methods now support anindex
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, whilefoo.where(:bar)
will return a new object leavingfoo
unchanged,foo.where!(:bar)
will mutate the foo objectJon 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:
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 ofSchemaCache
instance because we want to boot rails more quickly when we have many models.Usage notes:
-
execute rake task. RAILS_ENV=production bundle exec rake db:schema:cache:dump => generate db/schema_cache.dump
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add config.active_record.use_schema_cache_dump = true in config/production.rb. BTW, true is default.
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boot rails. RAILS_ENV=production bundle exec rails server => use db/schema_cache.dump
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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 awhere
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.includes(:comments).where(comments: { name: 'foo' }) Post.includes(:comments).where('comments.name' => 'foo') Post.includes(:comments).order('comments.name')
You 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 toschema_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
-
PostgreSQL hstore records can be created.
Aaron Patterson
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PostgreSQL hstore types are automatically deserialized from the database.
Aaron Patterson
Please check 3-2-stable for previous changes.