activerecord - gem.sh

Rails 6.1.3.1 (March 26, 2021)

No changes.

Rails 6.1.3 (February 17, 2021)

Fix the MySQL adapter to always set the right collation and charset
to the connection session.

Rafael Mendonça França
Fix MySQL adapter handling of time objects when prepared statements
are enabled.

Rafael Mendonça França
Fix scoping in enum fields using conditions that would generate
an IN clause.

Ryuta Kamizono
Skip optimised #exist? query when #include? is called on a relation
with a having clause

Relations that have aliased select values AND a having clause that
references an aliased select value would generate an error when

include? was called, due to an optimisation that would generate

call #exists? on the relation instead, which effectively alters
the select values of the query (and thus removes the aliased select
values), but leaves the having clause intact. Because the having
clause is then referencing an aliased column that is no longer
present in the simplified query, an ActiveRecord::InvalidStatement
error was raised.

An sample query affected by this problem:
```
Author.select('COUNT(*) as total_posts', 'authors.*')
      .joins(:posts)
      .group(:id)
      .having('total_posts &gt; 2')
      .include?(Author.first)
```
This change adds an addition check to the condition that skips the
simplified #exists? query, which simply checks for the presence of
a having clause.

Fixes #41417

Michael Smart
Increment postgres prepared statement counter before making a prepared statement, so if the statement is aborted
without Rails knowledge (e.g., if app gets kill -9d during long-running query or due to Rack::Timeout), app won’t end
up in perpetual crash state for being inconsistent with Postgres.

wbharding, Martin Tepper

Rails 6.1.2.1 (February 10, 2021)

Fix possible DoS vector in PostgreSQL money type

Carefully crafted input can cause a DoS via the regular expressions used
for validating the money format in the PostgreSQL adapter. This patch
fixes the regexp.

Thanks to @dee-see from Hackerone for this patch!

[CVE-2021-22880]

Aaron Patterson

Rails 6.1.2 (February 09, 2021)

Fix timestamp type for sqlite3.

Eileen M. Uchitelle
Make destroy async transactional.

An active record rollback could occur while enqueuing a job. In this
case the job would enqueue even though the database deletion
rolledback putting things in a funky state.

Now the jobs are only enqueued until after the db transaction has been committed.

Cory Gwin
Fix malformed packet error in MySQL statement for connection configuration.

robinroestenburg
Connection specification now passes the “url” key as a configuration for the
adapter if the “url” protocol is “jdbc”, “http”, or “https”. Previously only
urls with the “jdbc” prefix were passed to the Active Record Adapter, others
are assumed to be adapter specification urls.

Fixes #41137.

Jonathan Bracy
Fix granular connection swapping when there are multiple abstract classes.

Eileen M. Uchitelle
Fix find_by with custom primary key for belongs_to association.

Ryuta Kamizono
Add support for rails console --sandbox for multiple database applications.

alpaca-tc
Fix where on polymorphic association with empty array.

Ryuta Kamizono
Fix preventing writes for ApplicationRecord.

Eileen M. Uchitelle

Rails 6.1.1 (January 07, 2021)

Fix fixtures loading when strict loading is enabled for the association.

Alex Ghiculescu
Fix where with custom primary key for belongs_to association.

Ryuta Kamizono
Fix where with aliased associations.

Ryuta Kamizono
Fix composed_of with symbol mapping.

Ryuta Kamizono
Don’t skip money’s type cast for pluck and calculations.

Ryuta Kamizono
Fix where on polymorphic association with non Active Record object.

Ryuta Kamizono
Make sure db:prepare works even the schema file doesn’t exist.

Rafael Mendonça França
Fix complicated has_many :through with nested where condition.

Ryuta Kamizono
Handle STI models for has_many dependent: :destroy_async.

Muhammad Usman
Restore possibility of passing false to :polymorphic option of belongs_to.

Previously, passing false would trigger the option validation logic
to throw an error saying :polymorphic would not be a valid option.

glaszig
Allow adding nonnamed expression indexes to be revertible.

Fixes #40732.

Previously, the following code would raise an error, when executed while rolling back,
and the index name should be specified explicitly. Now, the index name is inferred
automatically.
```
add_index(:items, "to_tsvector('english', description)")
```
fatkodima

Rails 6.1.0 (December 09, 2020)

Only warn about negative enums if a positive form that would cause conflicts exists.

Fixes #39065.

Alex Ghiculescu
Change attribute_for_inspect to take filter_attributes in consideration.

Rafael Mendonça França
Fix odd behavior of inverse_of with multiple belongs_to to same class.

Fixes #35204.

Tomoyuki Kai
Build predicate conditions with objects that delegate #id and primary key:
```
class AdminAuthor
  delegate_missing_to :@author

  def initialize(author)
    @author = author
  end
end

Post.where(author: AdminAuthor.new(author))
```
Sean Doyle
Add connected_to_many API.

This API allows applications to connect to multiple databases at once without switching all of them or implementing a deeply nested stack.

Before:

AnimalsRecord.connected_to(role: :reading) do
MealsRecord.connected_to(role: :reading) do
Dog.first # read from animals replica
Dinner.first # read from meals replica
Person.first # read from primary writer
end
end

After:

ActiveRecord::Base.connected_to_many([AnimalsRecord, MealsRecord], role: :reading) do
Dog.first # read from animals replica
Dinner.first # read from meals replica
Person.first # read from primary writer
end

Eileen M. Uchitelle, John Crepezzi
Add option to raise or log for ActiveRecord::StrictLoadingViolationError.

Some applications may not want to raise an error in production if using strict_loading. This would allow an application to set strict loading to log for the production environment while still raising in development and test environments.

Set config.active_record.action_on_strict_loading_violation to :log errors instead of raising.

Eileen M. Uchitelle
Allow the inverse of a has_one association that was previously autosaved to be loaded.

Fixes #34255.

Steven Weber
Optimise the length of index names for polymorphic references by using the reference name rather than the type and id column names.

Because the default behaviour when adding an index with multiple columns is to use all column names in the index name, this could frequently lead to overly long index names for polymorphic references which would fail the migration if it exceeded the database limit.

This change reduces the chance of that happening by using the reference name, e.g. index_my_table_on_my_reference.

Fixes #38655.

Luke Redpath
MySQL: Uniqueness validator now respects default database collation,
no longer enforce case sensitive comparison by default.

Ryuta Kamizono
Remove deprecated methods from ActiveRecord::ConnectionAdapters::DatabaseLimits.

column_name_length
table_name_length
columns_per_table
indexes_per_table
columns_per_multicolumn_index
sql_query_length
joins_per_query

Rafael Mendonça França
Remove deprecated ActiveRecord::ConnectionAdapters::AbstractAdapter#supports_multi_insert?.

Rafael Mendonça França
Remove deprecated ActiveRecord::ConnectionAdapters::AbstractAdapter#supports_foreign_keys_in_create?.

Rafael Mendonça França
Remove deprecated ActiveRecord::ConnectionAdapters::PostgreSQLAdapter#supports_ranges?.

Rafael Mendonça França
Remove deprecated ActiveRecord::Base#update_attributes and ActiveRecord::Base#update_attributes!.

Rafael Mendonça França
Remove deprecated migrations_path argument in ActiveRecord::ConnectionAdapter::SchemaStatements#assume_migrated_upto_version.

Rafael Mendonça França
Remove deprecated config.active_record.sqlite3.represent_boolean_as_integer.

Rafael Mendonça França
relation.create does no longer leak scope to class level querying methods
in initialization block and callbacks.

Before:

User.where(name: “John”).create do |john|
User.find_by(name: “David”) # => nil
end

After:

User.where(name: “John”).create do |john|
User.find_by(name: “David”) # => #
end

Ryuta Kamizono
Named scope chain does no longer leak scope to class level querying methods.

class User < ActiveRecord::Base
scope :david, -> { User.where(name: “David”) }
end

Before:

User.where(name: “John”).david
# SELECT * FROM users WHERE name = ‘John’ AND name = ‘David’

After:

User.where(name: “John”).david
# SELECT * FROM users WHERE name = ‘David’

Ryuta Kamizono
Remove deprecated methods from ActiveRecord::DatabaseConfigurations.

fetch
each
first
values
[]=

Rafael Mendonça França
where.not now generates NAND predicates instead of NOR.

Before:

User.where.not(name: “Jon”, role: “admin”)
# SELECT * FROM users WHERE name != ‘Jon’ AND role != ‘admin’

After:

User.where.not(name: “Jon”, role: “admin”)
# SELECT * FROM users WHERE NOT (name == ‘Jon’ AND role == ‘admin’)

Rafael Mendonça França
Remove deprecated ActiveRecord::Result#to_hash method.

Rafael Mendonça França
Deprecate ActiveRecord::Base.allow_unsafe_raw_sql.

Rafael Mendonça França
Remove deprecated support for using unsafe raw SQL in ActiveRecord::Relation methods.

Rafael Mendonça França
Allow users to silence the “Rails couldn’t infer whether you are using multiple databases…”
message using config.active_record.suppress_multiple_database_warning.

Omri Gabay
Connections can be granularly switched for abstract classes when connected_to is called.

This change allows connected_to to switch a role and/or shard for a single abstract class instead of all classes globally. Applications that want to use the new feature need to set config.active_record.legacy_connection_handling to false in their application configuration.

Example usage:

Given an application we have a User model that inherits from ApplicationRecord and a Dog model that inherits from AnimalsRecord. AnimalsRecord and ApplicationRecord have writing and reading connections as well as shard default, one, and two.
```
ActiveRecord::Base.connected_to(role: :reading) do
  User.first # reads from default replica
  Dog.first # reads from default replica

  AnimalsRecord.connected_to(role: :writing, shard: :one) do
    User.first # reads from default replica
    Dog.first # reads from shard one primary
  end

  User.first # reads from default replica
  Dog.first # reads from default replica

  ApplicationRecord.connected_to(role: :writing, shard: :two) do
    User.first # reads from shard two primary
    Dog.first # reads from default replica
  end
end
```
Eileen M. Uchitelle, John Crepezzi
Allow double-dash comment syntax when querying read-only databases

James Adam
Add values_at method.

Returns an array containing the values associated with the given methods.
```
topic = Topic.first
topic.values_at(:title, :author_name)
# =&gt; ["Budget", "Jason"]
```
Similar to Hash#values_at but on an Active Record instance.

Guillaume Briday
Fix read_attribute_before_type_cast to consider attribute aliases.

Marcelo Lauxen
Support passing record to uniqueness validator :conditions callable:
```
class Article &lt; ApplicationRecord
  validates_uniqueness_of :title, conditions: -&gt;(article) {
    published_at = article.published_at
    where(published_at: published_at.beginning_of_year..published_at.end_of_year)
  }
end
```
Eliot Sykes
BatchEnumerator#update_all and BatchEnumerator#delete_all now return the
total number of rows affected, just like their non-batched counterparts.
```
Person.in_batches.update_all("first_name = 'Eugene'") # =&gt; 42
Person.in_batches.delete_all # =&gt; 42
```
Fixes #40287.

Eugene Kenny
Add support for PostgreSQL interval data type with conversion to
ActiveSupport::Duration when loading records from database and
serialization to ISO 8601 formatted duration string on save.
Add support to define a column in migrations and get it in a schema dump.
Optional column precision is supported.

To use this in 6.1, you need to place the next string to your model file:

attribute :duration, :interval

To keep old behavior until 6.2 is released:

attribute :duration, :string

Example:

create_table :events do |t|
t.string :name
t.interval :duration
end

class Event < ApplicationRecord
attribute :duration, :interval
end

Event.create!(name: ‘Rock Fest’, duration: 2.days)
Event.last.duration # => 2 days
Event.last.duration.iso8601 # => “P2D”
Event.new(duration: ‘P1DT12H3S’).duration # => 1 day, 12 hours, and 3 seconds
Event.new(duration: ‘1 day’) # Unknown value will be ignored and NULL will be written to database

Andrey Novikov
Allow associations supporting the dependent: key to take dependent: :destroy_async.
```
class Account &lt; ActiveRecord::Base
    belongs_to :supplier, dependent: :destroy_async
end
```
:destroy_async will enqueue a job to destroy associated records in the background.

DHH, George Claghorn, Cory Gwin, Rafael Mendonça França, Adrianna Chang
Add SKIP_TEST_DATABASE environment variable to disable modifying the test database when rails db:create and rails db:drop are called.

Jason Schweier
connects_to can only be called on ActiveRecord::Base or abstract classes.

Ensure that connects_to can only be called from ActiveRecord::Base or abstract classes. This protects the application from opening duplicate or too many connections.

Eileen M. Uchitelle, John Crepezzi
All connection adapters execute now raises ActiveRecord::ConnectionNotEstablished rather than
ActiveRecord::StatementInvalid when they encounter a connection error.

Jean Boussier
Mysql2Adapter#quote_string now raises ActiveRecord::ConnectionNotEstablished rather than
ActiveRecord::StatementInvalid when it can’t connect to the MySQL server.

Jean Boussier
Add support for check constraints that are NOT VALID via validate: false (PostgreSQL-only).

Alex Robbin
Ensure the default configuration is considered primary or first for an environment

If a multiple database application provides a configuration named primary, that will be treated as default. In applications that do not have a primary entry, the default database configuration will be the first configuration for an environment.

Eileen M. Uchitelle
Allow where references association names as joined table name aliases.
```
class Comment &lt; ActiveRecord::Base
  enum label: [:default, :child]
  has_many :children, class_name: "Comment", foreign_key: :parent_id
end

# ... FROM comments LEFT OUTER JOIN comments children ON ... WHERE children.label = 1
Comment.includes(:children).where("children.label": "child")
```
Ryuta Kamizono
Support storing demodulized class name for polymorphic type.

Before Rails 6.1, storing demodulized class name is supported only for STI type
by store_full_sti_class class attribute.

Now store_full_class_name class attribute can handle both STI and polymorphic types.

Ryuta Kamizono
Deprecate rails db:structure:{load, dump} tasks and extend
rails db:schema:{load, dump} tasks to work with either :ruby or :sql format,
depending on config.active_record.schema_format configuration value.

fatkodima
Respect the select values for eager loading.
```
post = Post.select("UPPER(title) AS title").first
post.title # =&gt; "WELCOME TO THE WEBLOG"
post.body  # =&gt; ActiveModel::MissingAttributeError

# Rails 6.0 (ignore the `select` values)
post = Post.select("UPPER(title) AS title").eager_load(:comments).first
post.title # =&gt; "Welcome to the weblog"
post.body  # =&gt; "Such a lovely day"

# Rails 6.1 (respect the `select` values)
post = Post.select("UPPER(title) AS title").eager_load(:comments).first
post.title # =&gt; "WELCOME TO THE WEBLOG"
post.body  # =&gt; ActiveModel::MissingAttributeError
```
Ryuta Kamizono
Allow attribute’s default to be configured but keeping its own type.
```
class Post &lt; ActiveRecord::Base
  attribute :written_at, default: -&gt; { Time.now.utc }
end

# Rails 6.0
Post.type_for_attribute(:written_at) # =&gt; #

# Rails 6.1
Post.type_for_attribute(:written_at) # =&gt; #
```
Ryuta Kamizono
Allow default to be configured for Enum.
```
class Book &lt; ActiveRecord::Base
  enum status: [:proposed, :written, :published], _default: :published
end

Book.new.status # =&gt; "published"
```
Ryuta Kamizono
Deprecate YAML loading from legacy format older than Rails 5.0.

Ryuta Kamizono
Added the setting ActiveRecord::Base.immutable_strings_by_default, which
allows you to specify that all string columns should be frozen unless
otherwise specified. This will reduce memory pressure for applications which
do not generally mutate string properties of Active Record objects.

Sean Griffin, Ryuta Kamizono
Deprecate map! and collect! on ActiveRecord::Result.

Ryuta Kamizono
Support relation.and for intersection as Set theory.
```
david_and_mary = Author.where(id: [david, mary])
mary_and_bob   = Author.where(id: [mary, bob])

david_and_mary.merge(mary_and_bob) # =&gt; [mary, bob]

david_and_mary.and(mary_and_bob) # =&gt; [mary]
david_and_mary.or(mary_and_bob)  # =&gt; [david, mary, bob]
```
Ryuta Kamizono
Merging conditions on the same column no longer maintain both conditions,
and will be consistently replaced by the latter condition in Rails 6.2.
To migrate to Rails 6.2’s behavior, use relation.merge(other, rewhere: true).
```
# Rails 6.1 (IN clause is replaced by merger side equality condition)
Author.where(id: [david.id, mary.id]).merge(Author.where(id: bob)) # =&gt; [bob]

# Rails 6.1 (both conflict conditions exists, deprecated)
Author.where(id: david.id..mary.id).merge(Author.where(id: bob)) # =&gt; []

# Rails 6.1 with rewhere to migrate to Rails 6.2's behavior
Author.where(id: david.id..mary.id).merge(Author.where(id: bob), rewhere: true) # =&gt; [bob]

# Rails 6.2 (same behavior with IN clause, mergee side condition is consistently replaced)
Author.where(id: [david.id, mary.id]).merge(Author.where(id: bob)) # =&gt; [bob]
Author.where(id: david.id..mary.id).merge(Author.where(id: bob)) # =&gt; [bob]
```
Ryuta Kamizono
Do not mark Postgresql MAC address and UUID attributes as changed when the assigned value only varies by case.

Peter Fry
Resolve issue with insert_all unique_by option when used with expression index.

When the :unique_by option of ActiveRecord::Persistence.insert_all and
ActiveRecord::Persistence.upsert_all was used with the name of an expression index, an error
was raised. Adding a guard around the formatting behavior for the :unique_by corrects this.

Usage:
```
create_table :books, id: :integer, force: true do |t|
  t.column :name, :string
  t.index "lower(name)", unique: true
end

Book.insert_all [{ name: "MyTest" }], unique_by: :index_books_on_lower_name
```
Fixes #39516.

Austen Madden
Add basic support for CHECK constraints to database migrations.

Usage:
```
add_check_constraint :products, "price &gt; 0", name: "price_check"
remove_check_constraint :products, name: "price_check"
```
fatkodima
Add ActiveRecord::Base.strict_loading_by_default and ActiveRecord::Base.strict_loading_by_default=
to enable/disable strict_loading mode by default for a model. The configuration’s value is
inheritable by subclasses, but they can override that value and it will not impact parent class.

Usage:
```
class Developer &lt; ApplicationRecord
  self.strict_loading_by_default = true

  has_many :projects
end

dev = Developer.first
dev.projects.first
# =&gt; ActiveRecord::StrictLoadingViolationError Exception: Developer is marked as strict_loading and Project cannot be lazily loaded.
```
bogdanvlviv
Deprecate passing an Active Record object to quote/type_cast directly.

Ryuta Kamizono
Default engine ENGINE=InnoDB is no longer dumped to make schema more agnostic.

Before:
```
create_table "accounts", options: "ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci", force: :cascade do |t|
end
```
After:
```
create_table "accounts", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
end
```
Ryuta Kamizono
Added delegated type as an alternative to single-table inheritance for representing class hierarchies.
See ActiveRecord::DelegatedType for the full description.

DHH
Deprecate aggregations with group by duplicated fields.

To migrate to Rails 6.2’s behavior, use uniq!(:group) to deduplicate group fields.
```
accounts = Account.group(:firm_id)

# duplicated group fields, deprecated.
accounts.merge(accounts.where.not(credit_limit: nil)).sum(:credit_limit)
# =&gt; {
#   [1, 1] =&gt; 50,
#   [2, 2] =&gt; 60
# }

# use `uniq!(:group)` to deduplicate group fields.
accounts.merge(accounts.where.not(credit_limit: nil)).uniq!(:group).sum(:credit_limit)
# =&gt; {
#   1 =&gt; 50,
#   2 =&gt; 60
# }
```
Ryuta Kamizono
Deprecate duplicated query annotations.

To migrate to Rails 6.2’s behavior, use uniq!(:annotate) to deduplicate query annotations.
```
accounts = Account.where(id: [1, 2]).annotate("david and mary")

# duplicated annotations, deprecated.
accounts.merge(accounts.rewhere(id: 3))
# SELECT accounts.* FROM accounts WHERE accounts.id = 3 /* david and mary */ /* david and mary */

# use `uniq!(:annotate)` to deduplicate annotations.
accounts.merge(accounts.rewhere(id: 3)).uniq!(:annotate)
# SELECT accounts.* FROM accounts WHERE accounts.id = 3 /* david and mary */
```
Ryuta Kamizono
Resolve conflict between counter cache and optimistic locking.

Bump an Active Record instance’s lock version after updating its counter
cache. This avoids raising an unnecessary ActiveRecord::StaleObjectError
upon subsequent transactions by maintaining parity with the corresponding
database record’s lock_version column.

Fixes #16449.

Aaron Lipman
Support merging option :rewhere to allow mergee side condition to be replaced exactly.
```
david_and_mary = Author.where(id: david.id..mary.id)

# both conflict conditions exists
david_and_mary.merge(Author.where(id: bob)) # =&gt; []

# mergee side condition is replaced by rewhere
david_and_mary.merge(Author.rewhere(id: bob)) # =&gt; [bob]

# mergee side condition is replaced by rewhere option
david_and_mary.merge(Author.where(id: bob), rewhere: true) # =&gt; [bob]
```
Ryuta Kamizono
Add support for finding records based on signed ids, which are tamper-proof, verified ids that can be
set to expire and scoped with a purpose. This is particularly useful for things like password reset
or email verification, where you want the bearer of the signed id to be able to interact with the
underlying record, but usually only within a certain time period.
```
signed_id = User.first.signed_id expires_in: 15.minutes, purpose: :password_reset

User.find_signed signed_id # =&gt; nil, since the purpose does not match

travel 16.minutes
User.find_signed signed_id, purpose: :password_reset # =&gt; nil, since the signed id has expired

travel_back
User.find_signed signed_id, purpose: :password_reset # =&gt; User.first

User.find_signed! "bad data" # =&gt; ActiveSupport::MessageVerifier::InvalidSignature
```
DHH
Support ALGORITHM = INSTANT DDL option for index operations on MySQL.

Ryuta Kamizono
Fix index creation to preserve index comment in bulk change table on MySQL.

Ryuta Kamizono
Allow unscope to be aware of table name qualified values.

It is possible to unscope only the column in the specified table.
```
posts = Post.joins(:comments).group(:"posts.hidden")
posts = posts.where("posts.hidden": false, "comments.hidden": false)

posts.count
# =&gt; { false =&gt; 10 }

# unscope both hidden columns
posts.unscope(where: :hidden).count
# =&gt; { false =&gt; 11, true =&gt; 1 }

# unscope only comments.hidden column
posts.unscope(where: :"comments.hidden").count
# =&gt; { false =&gt; 11 }
```
Ryuta Kamizono, Slava Korolev
Fix rewhere to truly overwrite collided where clause by new where clause.
```
steve = Person.find_by(name: "Steve")
david = Author.find_by(name: "David")

relation = Essay.where(writer: steve)

# Before
relation.rewhere(writer: david).to_a # =&gt; []

# After
relation.rewhere(writer: david).to_a # =&gt; [david]
```
Ryuta Kamizono
Inspect time attributes with subsec and time zone offset.
```
p Knot.create
=&gt; #
```
akinomaeni, Jonathan Hefner
Deprecate passing a column to type_cast.

Ryuta Kamizono
Deprecate in_clause_length and allowed_index_name_length in DatabaseLimits.

Ryuta Kamizono
Support bulk insert/upsert on relation to preserve scope values.

Josef Šimánek, Ryuta Kamizono
Preserve column comment value on changing column name on MySQL.

Islam Taha
Add support for if_exists option for removing an index.

The remove_index method can take an if_exists option. If this is set to true an error won’t be raised if the index doesn’t exist.

Eileen M. Uchitelle
Remove ibm_db, informix, mssql, oracle, and oracle12 Arel visitors which are not used in the code base.

Ryuta Kamizono
Prevent build_association from touching a parent record if the record isn’t persisted for has_one associations.

Fixes #38219.

Josh Brody
Add support for if_not_exists option for adding index.

The add_index method respects if_not_exists option. If it is set to true
index won’t be added.

Usage:
```
  add_index :users, :account_id, if_not_exists: true
```
The if_not_exists option passed to create_table also gets propagated to indexes
created within that migration so that if table and its indexes exist then there is no
attempt to create them again.

Prathamesh Sonpatki
Add ActiveRecord::Base#previously_new_record? to show if a record was new before the last save.

Tom Ward
Support descending order for find_each, find_in_batches, and in_batches.

Batch processing methods allow you to work with the records in batches, greatly reducing memory consumption, but records are always batched from oldest id to newest.

This change allows reversing the order, batching from newest to oldest. This is useful when you need to process newer batches of records first.

Pass order: :desc to yield batches in descending order. The default remains order: :asc.
```
Person.find_each(order: :desc) do |person|
  person.party_all_night!
end
```
Alexey Vasiliev
Fix insert_all with enum values.

Fixes #38716.

Joel Blum
Add support for db:rollback:name for multiple database applications.

Multiple database applications will now raise if db:rollback is call and recommend using the db:rollback:[NAME] to rollback migrations.

Eileen M. Uchitelle
Relation#pick now uses already loaded results instead of making another query.

Eugene Kenny
Deprecate using return, break or throw to exit a transaction block after writes.

Dylan Thacker-Smith
Dump the schema or structure of a database when calling db:migrate:name.

In previous versions of Rails, rails db:migrate would dump the schema of the database. In Rails 6, that holds true (rails db:migrate dumps all databases’ schemas), but rails db:migrate:name does not share that behavior.

Going forward, calls to rails db:migrate:name will dump the schema (or structure) of the database being migrated.

Kyle Thompson
Reset the ActiveRecord::Base connection after rails db:migrate:name.

When rails db:migrate has finished, it ensures the ActiveRecord::Base connection is reset to its original configuration. Going forward, rails db:migrate:name will have the same behavior.

Kyle Thompson
Disallow calling connected_to on subclasses of ActiveRecord::Base.

Behavior has not changed here but the previous API could be misleading to people who thought it would switch connections for only that class. connected_to switches the context from which we are getting connections, not the connections themselves.

Eileen M. Uchitelle, John Crepezzi
Add support for horizontal sharding to connects_to and connected_to.

Applications can now connect to multiple shards and switch between their shards in an application. Note that the shard swapping is still a manual process as this change does not include an API for automatic shard swapping.

Usage:

Given the following configuration:
```
# config/database.yml
production:
  primary:
    database: my_database
  primary_shard_one:
    database: my_database_shard_one
```
Connect to multiple shards:
```
class ApplicationRecord &lt; ActiveRecord::Base
  self.abstract_class = true

  connects_to shards: {
    default: { writing: :primary },
    shard_one: { writing: :primary_shard_one }
  }
```
Swap between shards in your controller / model code:
```
ActiveRecord::Base.connected_to(shard: :shard_one) do
  # Read from shard one
end
```
The horizontal sharding API also supports read replicas. See guides for more details.

Eileen M. Uchitelle, John Crepezzi
Deprecate spec_name in favor of name on database configurations.

The accessors for spec_name on configs_for and DatabaseConfig are deprecated. Please use name instead.

Deprecated behavior:
```
db_config = ActiveRecord::Base.configs_for(env_name: "development", spec_name: "primary")
db_config.spec_name
```
New behavior:
```
db_config = ActiveRecord::Base.configs_for(env_name: "development", name: "primary")
db_config.name
```
Eileen M. Uchitelle
Add additional database-specific rake tasks for multi-database users.

Previously, rails db:create, rails db:drop, and rails db:migrate were the only rails tasks that could operate on a single
database. For example:
```
rails db:create
rails db:create:primary
rails db:create:animals
rails db:drop
rails db:drop:primary
rails db:drop:animals
rails db:migrate
rails db:migrate:primary
rails db:migrate:animals
```
With these changes, rails db:schema:dump, rails db:schema:load, rails db:structure:dump, rails db:structure:load and
rails db:test:prepare can additionally operate on a single database. For example:
```
rails db:schema:dump
rails db:schema:dump:primary
rails db:schema:dump:animals
rails db:schema:load
rails db:schema:load:primary
rails db:schema:load:animals
rails db:structure:dump
rails db:structure:dump:primary
rails db:structure:dump:animals
rails db:structure:load
rails db:structure:load:primary
rails db:structure:load:animals
rails db:test:prepare
rails db:test:prepare:primary
rails db:test:prepare:animals
```
Kyle Thompson
Add support for strict_loading mode on association declarations.

Raise an error if attempting to load a record from an association that has been marked as strict_loading unless it was explicitly eager loaded.

Usage:
```
class Developer &lt; ApplicationRecord
  has_many :projects, strict_loading: true
end

dev = Developer.first
dev.projects.first
# =&gt; ActiveRecord::StrictLoadingViolationError: The projects association is marked as strict_loading and cannot be lazily loaded.
```
Kevin Deisz
Add support for strict_loading mode to prevent lazy loading of records.

Raise an error if a parent record is marked as strict_loading and attempts to lazily load its associations. This is useful for finding places you may want to preload an association and avoid additional queries.

Usage:
```
dev = Developer.strict_loading.first
dev.audit_logs.to_a
# =&gt; ActiveRecord::StrictLoadingViolationError: Developer is marked as strict_loading and AuditLog cannot be lazily loaded.
```
Eileen M. Uchitelle, Aaron Patterson
Add support for PostgreSQL 11+ partitioned indexes when using upsert_all.

Sebastián Palma
Adds support for if_not_exists to add_column and if_exists to remove_column.

Applications can set their migrations to ignore exceptions raised when adding a column that already exists or when removing a column that does not exist.

Example Usage:
```
class AddColumnTitle &lt; ActiveRecord::Migration[6.1]
  def change
    add_column :posts, :title, :string, if_not_exists: true
  end
end
```
```
class RemoveColumnTitle &lt; ActiveRecord::Migration[6.1]
  def change
    remove_column :posts, :title, if_exists: true
  end
end
```
Eileen M. Uchitelle
Regexp-escape table name for MS SQL Server.

Add Regexp.escape to one method in ActiveRecord, so that table names with regular expression characters in them work as expected. Since MS SQL Server uses “[” and “]” to quote table and column names, and those characters are regular expression characters, methods like pluck and select fail in certain cases when used with the MS SQL Server adapter.

Larry Reid
Store advisory locks on their own named connection.

Previously advisory locks were taken out against a connection when a migration started. This works fine in single database applications but doesn’t work well when migrations need to open new connections which results in the lock getting dropped.

In order to fix this we are storing the advisory lock on a new connection with the connection specification name AdvisoryLockBase. The caveat is that we need to maintain at least 2 connections to a database while migrations are running in order to do this.

Eileen M. Uchitelle, John Crepezzi
Allow schema cache path to be defined in the database configuration file.

For example:
```
development:
  adapter: postgresql
  database: blog_development
  pool: 5
  schema_cache_path: tmp/schema/main.yml
```
Katrina Owen
Deprecate #remove_connection in favor of #remove_connection_pool when called on the handler.

#remove_connection is deprecated in order to support returning a DatabaseConfig object instead of a Hash. Use #remove_connection_pool, #remove_connection will be removed in 6.2.

Eileen M. Uchitelle, John Crepezzi
Deprecate #default_hash and it’s alias #[] on database configurations.

Applications should use configs_for. #default_hash and #[] will be removed in 6.2.

Eileen M. Uchitelle, John Crepezzi
Add scale support to ActiveRecord::Validations::NumericalityValidator.

Gannon McGibbon
Find orphans by looking for missing relations through chaining where.missing:

Before:
```
Post.left_joins(:author).where(authors: { id: nil })
```
After:
```
Post.where.missing(:author)
```
Tom Rossi
Ensure :reading connections always raise if a write is attempted.

Now Rails will raise an ActiveRecord::ReadOnlyError if any connection on the reading handler attempts to make a write. If your reading role needs to write you should name the role something other than :reading.

Eileen M. Uchitelle
Deprecate "primary" as the connection_specification_name for ActiveRecord::Base.

"primary" has been deprecated as the connection_specification_name for ActiveRecord::Base in favor of using "ActiveRecord::Base". This change affects calls to ActiveRecord::Base.connection_handler.retrieve_connection and ActiveRecord::Base.connection_handler.remove_connection. If you’re calling these methods with "primary", please switch to "ActiveRecord::Base".

Eileen M. Uchitelle, John Crepezzi
Add ActiveRecord::Validations::NumericalityValidator with
support for casting floats using a database columns’ precision value.

Gannon McGibbon
Enforce fresh ETag header after a collection’s contents change by adding
ActiveRecord::Relation#cache_key_with_version. This method will be used by
ActionController::ConditionalGet to ensure that when collection cache versioning
is enabled, requests using ConditionalGet don’t return the same ETag header
after a collection is modified.

Fixes #38078.

Aaron Lipman
Skip test database when running db:create or db:drop in development
with DATABASE_URL set.

Brian Buchalter
Don’t allow mutations on the database configurations hash.

Freeze the configurations hash to disallow directly changing it. If applications need to change the hash, for example to create databases for parallelization, they should use the DatabaseConfig object directly.

Before:
```
@db_config = ActiveRecord::Base.configurations.configs_for(env_name: "test", spec_name: "primary")
@db_config.configuration_hash.merge!(idle_timeout: "0.02")
```
After:
```
@db_config = ActiveRecord::Base.configurations.configs_for(env_name: "test", spec_name: "primary")
config = @db_config.configuration_hash.merge(idle_timeout: "0.02")
db_config = ActiveRecord::DatabaseConfigurations::HashConfig.new(@db_config.env_name, @db_config.spec_name, config)
```
Eileen M. Uchitelle, John Crepezzi
Remove :connection_id from the sql.active_record notification.

Aaron Patterson, Rafael Mendonça França
The :name key will no longer be returned as part of DatabaseConfig#configuration_hash. Please use DatabaseConfig#owner_name instead.

Eileen M. Uchitelle, John Crepezzi
ActiveRecord’s belongs_to_required_by_default flag can now be set per model.

You can now opt-out/opt-in specific models from having their associations required
by default.

This change is meant to ease the process of migrating all your models to have
their association required.

Edouard Chin
The connection_config method has been deprecated, please use connection_db_config instead which will return a DatabaseConfigurations::DatabaseConfig instead of a Hash.

Eileen M. Uchitelle, John Crepezzi
Retain explicit selections on the base model after applying includes and joins.

Resolves #34889.

Patrick Rebsch
The database kwarg is deprecated without replacement because it can’t be used for sharding and creates an issue if it’s used during a request. Applications that need to create new connections should use connects_to instead.

Eileen M. Uchitelle, John Crepezzi
Allow attributes to be fetched from Arel node groupings.

Jeff Emminger, Gannon McGibbon
A database URL can now contain a querystring value that contains an equal sign. This is needed to support passing PostgreSQL options.

Joshua Flanagan
Calling methods like establish_connection with a Hash which is invalid (eg: no adapter) will now raise an error the same way as connections defined in config/database.yml.

John Crepezzi
Specifying implicit_order_column now subsorts the records by primary key if available to ensure deterministic results.

Paweł Urbanek
where(attr => []) now loads an empty result without making a query.

John Hawthorn
Fixed the performance regression for primary_keys introduced MySQL 8.0.

Hiroyuki Ishii
Add support for belongs_to to has_many inversing.

Gannon McGibbon
Allow length configuration for has_secure_token method. The minimum length
is set at 24 characters.

Before:
```
has_secure_token :auth_token
```
After:
```
has_secure_token :default_token             # 24 characters
has_secure_token :auth_token, length: 36    # 36 characters
has_secure_token :invalid_token, length: 12 # =&gt; ActiveRecord::SecureToken::MinimumLengthError
```
Bernardo de Araujo
Deprecate DatabaseConfigurations#to_h. These connection hashes are still available via ActiveRecord::Base.configurations.configs_for.

Eileen Uchitelle, John Crepezzi
Add DatabaseConfig#configuration_hash to return database configuration hashes with symbol keys, and use all symbol-key configuration hashes internally. Deprecate DatabaseConfig#config which returns a String-keyed Hash with the same values.

John Crepezzi, Eileen Uchitelle
Allow column names to be passed to remove_index positionally along with other options.

Passing other options can be necessary to make remove_index correctly reversible.

Before:

add_index :reports, :report_id # => works
add_index :reports, :report_id, unique: true # => works
remove_index :reports, :report_id # => works
remove_index :reports, :report_id, unique: true # => ArgumentError

After:

remove_index :reports, :report_id, unique: true # => works

Eugene Kenny
Allow bulk ALTER statements to drop and recreate indexes with the same name.

Eugene Kenny
insert, insert_all, upsert, and upsert_all now clear the query cache.

Eugene Kenny
Call while_preventing_writes directly from connected_to.

In some cases application authors want to use the database switching middleware and make explicit calls with connected_to. It’s possible for an app to turn off writes and not turn them back on by the time we call connected_to(role: :writing).

This change allows apps to fix this by assuming if a role is writing we want to allow writes, except in the case it’s explicitly turned off.

Eileen M. Uchitelle
Improve detection of ActiveRecord::StatementTimeout with mysql2 adapter in the edge case when the query is terminated during filesort.

Kir Shatrov
Stop trying to read yaml file fixtures when loading Active Record fixtures.

Gannon McGibbon
Deprecate .reorder(nil) with .first / .first! taking non-deterministic result.

To continue taking non-deterministic result, use .take / .take! instead.

Ryuta Kamizono
Preserve user supplied joins order as much as possible.

Fixes #36761, #34328, #24281, #12953.

Ryuta Kamizono
Allow matches_regex and does_not_match_regexp on the MySQL Arel visitor.

James Pearson
Allow specifying fixtures to be ignored by setting ignore in YAML file’s ‘_fixture’ section.

Tongfei Gao
Make the DATABASE_URL env variable only affect the primary connection. Add new env variables for multiple databases.

John Crepezzi, Eileen Uchitelle
Add a warning for enum elements with ‘not_’ prefix.

class Foo
enum status: [:sent, :not_sent]
end

Edu Depetris
Make currency symbols optional for money column type in PostgreSQL.

Joel Schneider
Add support for beginless ranges, introduced in Ruby 2.7.

Josh Goodall
Add database_exists? method to connection adapters to check if a database exists.

Guilherme Mansur
Loading the schema for a model that has no table_name raises a TableNotSpecified error.

Guilherme Mansur, Eugene Kenny
PostgreSQL: Fix GROUP BY with ORDER BY virtual count attribute.

Fixes #36022.

Ryuta Kamizono
Make ActiveRecord ConnectionPool.connections method thread-safe.

Fixes #36465.

Jeff Doering
Add support for multiple databases to rails db:abort_if_pending_migrations.

Mark Lee
Fix sqlite3 collation parsing when using decimal columns.

Martin R. Schuster
Fix invalid schema when primary key column has a comment.

Fixes #29966.

Guilherme Goettems Schneider
Fix table comment also being applied to the primary key column.

Guilherme Goettems Schneider
Allow generated create_table migrations to include or skip timestamps.

Michael Duchemin

Please check 6-0-stable for previous changes.

Modules

Classes

Rails 6.1.3.1 (March 26, 2021)

Rails 6.1.3 (February 17, 2021)

include? was called, due to an optimisation that would generate

Rails 6.1.2.1 (February 10, 2021)

Rails 6.1.2 (February 09, 2021)

Rails 6.1.1 (January 07, 2021)

Rails 6.1.0 (December 09, 2020)

Top-Level Modules

Top-Level Instance Methods