ActiveRecord::Core

configurations()

Returns fully resolved ActiveRecord::DatabaseConfigurations object

📝 Source code

# File activerecord/lib/active_record/core.rb, line 56
      def self.configurations
        @@configurations
      end

🔎 See on GitHub

configurations=(config)

Contains the database configuration - as is typically stored in config/database.yml - as an ActiveRecord::DatabaseConfigurations object.

For example, the following database.yml…

development:
  adapter: sqlite3
  database: db/development.sqlite3

production:
  adapter: sqlite3
  database: db/production.sqlite3

…would result in ActiveRecord::Base.configurations to look like this:

#<ActiveRecord::DatabaseConfigurations:0x00007fd1acbdf800 @configurations=[
  #<ActiveRecord::DatabaseConfigurations::HashConfig:0x00007fd1acbded10 @env_name="development",
    @name="primary", @config={adapter: "sqlite3", database: "db/development.sqlite3"}>,
  #<ActiveRecord::DatabaseConfigurations::HashConfig:0x00007fd1acbdea90 @env_name="production",
    @name="primary", @config={adapter: "sqlite3", database: "db/production.sqlite3"}>
]>

📝 Source code

# File activerecord/lib/active_record/core.rb, line 50
      def self.configurations=(config)
        @@configurations = ActiveRecord::DatabaseConfigurations.new(config)
      end

🔎 See on GitHub

connection_handler()

📝 Source code

# File activerecord/lib/active_record/core.rb, line 94
      def self.connection_handler
        ActiveSupport::IsolatedExecutionState[:active_record_connection_handler] || default_connection_handler
      end

🔎 See on GitHub

connection_handler=(handler)

📝 Source code

# File activerecord/lib/active_record/core.rb, line 98
      def self.connection_handler=(handler)
        ActiveSupport::IsolatedExecutionState[:active_record_connection_handler] = handler
      end

🔎 See on GitHub

connection_handlers()

📝 Source code

# File activerecord/lib/active_record/core.rb, line 102
      def self.connection_handlers
        if ActiveRecord.legacy_connection_handling
        else
          raise NotImplementedError, "The new connection handling does not support accessing multiple connection handlers."
        end

        @@connection_handlers ||= {}
      end

🔎 See on GitHub

connection_handlers=(handlers)

📝 Source code

# File activerecord/lib/active_record/core.rb, line 111
      def self.connection_handlers=(handlers)
        if ActiveRecord.legacy_connection_handling
          ActiveSupport::Deprecation.warn(<<~MSG)
            Using legacy connection handling is deprecated. Please set
            `legacy_connection_handling` to `false` in your application.

            The new connection handling does not support `connection_handlers`
            getter and setter.

            Read more about how to migrate at: https://guides.rubyonrails.org/active_record_multiple_databases.html#migrate-to-the-new-connection-handling
          MSG
        else
          raise NotImplementedError, "The new connection handling does not support multiple connection handlers."
        end

        @@connection_handlers = handlers
      end

🔎 See on GitHub

current_preventing_writes()

Returns the symbol representing the current setting for preventing writes.

ActiveRecord::Base.connected_to(role: :reading) do
  ActiveRecord::Base.current_preventing_writes #=> true
end

ActiveRecord::Base.connected_to(role: :writing) do
  ActiveRecord::Base.current_preventing_writes #=> false
end

📝 Source code

# File activerecord/lib/active_record/core.rb, line 188
      def self.current_preventing_writes
        if ActiveRecord.legacy_connection_handling
          connection_handler.prevent_writes
        else
          connected_to_stack.reverse_each do |hash|
            return hash[:prevent_writes] if !hash[:prevent_writes].nil? && hash[:klasses].include?(Base)
            return hash[:prevent_writes] if !hash[:prevent_writes].nil? && hash[:klasses].include?(connection_class_for_self)
          end

          false
        end
      end

🔎 See on GitHub

current_role()

Returns the symbol representing the current connected role.

ActiveRecord::Base.connected_to(role: :writing) do
  ActiveRecord::Base.current_role #=> :writing
end

ActiveRecord::Base.connected_to(role: :reading) do
  ActiveRecord::Base.current_role #=> :reading
end

📝 Source code

# File activerecord/lib/active_record/core.rb, line 147
      def self.current_role
        if ActiveRecord.legacy_connection_handling
          connection_handlers.key(connection_handler) || default_role
        else
          connected_to_stack.reverse_each do |hash|
            return hash[:role] if hash[:role] && hash[:klasses].include?(Base)
            return hash[:role] if hash[:role] && hash[:klasses].include?(connection_class_for_self)
          end

          default_role
        end
      end

🔎 See on GitHub

current_shard()

Returns the symbol representing the current connected shard.

ActiveRecord::Base.connected_to(role: :reading) do
  ActiveRecord::Base.current_shard #=> :default
end

ActiveRecord::Base.connected_to(role: :writing, shard: :one) do
  ActiveRecord::Base.current_shard #=> :one
end

📝 Source code

# File activerecord/lib/active_record/core.rb, line 169
      def self.current_shard
        connected_to_stack.reverse_each do |hash|
          return hash[:shard] if hash[:shard] && hash[:klasses].include?(Base)
          return hash[:shard] if hash[:shard] && hash[:klasses].include?(connection_class_for_self)
        end

        default_shard
      end

🔎 See on GitHub

destroy_association_async_job

Specifies the job used to destroy associations in the background

📝 Source code

# File activerecord/lib/active_record/core.rb, line 26
      class_attribute :destroy_association_async_job, instance_writer: false, instance_predicate: false, default: false

🔎 See on GitHub

enumerate_columns_in_select_statements

Force enumeration of all columns in SELECT statements. e.g. SELECT first_name, last_name FROM ... instead of SELECT * FROM ... This avoids PreparedStatementCacheExpired errors when a column is added to the database while the app is running.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 66
      class_attribute :enumerate_columns_in_select_statements, instance_accessor: false, default: false

🔎 See on GitHub

logger

Accepts a logger conforming to the interface of Log4r which is then passed on to any new database connections made and which can be retrieved on both a class and instance level by calling logger.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 20
      class_attribute :logger, instance_writer: false

🔎 See on GitHub

new(attributes = nil)

New objects can be instantiated as either empty (pass no construction parameter) or pre-set with attributes but not yet saved (pass a hash with key names matching the associated table column names). In both instances, valid attribute keys are determined by the column names of the associated table – hence you can’t have attributes that aren’t part of the table columns.

Example:

# Instantiates a single new object
User.new(first_name: 'Jamie')

📝 Source code

# File activerecord/lib/active_record/core.rb, line 461
    def initialize(attributes = nil)
      @new_record = true
      @attributes = self.class._default_attributes.deep_dup

      init_internals
      initialize_internals_callback

      assign_attributes(attributes) if attributes

      yield self if block_given?
      _run_initialize_callbacks
    end

🔎 See on GitHub

<=>(other_object)

Allows sort on objects

📝 Source code

# File activerecord/lib/active_record/core.rb, line 614
    def <=>(other_object)
      if other_object.is_a?(self.class)
        to_key <=> other_object.to_key
      else
        super
      end
    end

🔎 See on GitHub

==(comparison_object)

Returns true if comparison_object is the same exact object, or comparison_object is of the same type and self has an ID and it is equal to comparison_object.id.

Note that new records are different from any other record by definition, unless the other record is the receiver itself. Besides, if you fetch existing records with select and leave the ID out, you’re on your own, this predicate will return false.

Note also that destroying a record preserves its ID in the model instance, so deleted models are still comparable.

Also aliased as: eql?

📝 Source code

# File activerecord/lib/active_record/core.rb, line 580
    def ==(comparison_object)
      super ||
        comparison_object.instance_of?(self.class) &&
        !id.nil? &&
        comparison_object.id == id
    end

🔎 See on GitHub

clone

Identical to Ruby’s clone method. This is a “shallow” copy. Be warned that your attributes are not copied. That means that modifying attributes of the clone will modify the original, since they will both point to the same attributes hash. If you need a copy of your attributes hash, please use the dup method.

user = User.first
new_user = user.clone
user.name               # => "Bob"
new_user.name = "Joe"
user.name               # => "Joe"

user.object_id == new_user.object_id            # => false
user.name.object_id == new_user.name.object_id  # => true

user.name.object_id == user.dup.name.object_id  # => false

🔎 See on GitHub

connection_handler()

📝 Source code

# File activerecord/lib/active_record/core.rb, line 682
    def connection_handler
      self.class.connection_handler
    end

🔎 See on GitHub

dup

Duped objects have no id assigned and are treated as new records. Note that this is a “shallow” copy as it copies the object’s attributes only, not its associations. The extent of a “deep” copy is application specific and is therefore left to the application to implement according to its need. The dup method does not preserve the timestamps (created|updated)_(at|on).

🔎 See on GitHub

encode_with(coder)

Populate coder with attributes about this record that should be serialized. The structure of coder defined in this method is guaranteed to match the structure of coder passed to the init_with method.

Example:

class Post < ActiveRecord::Base
end
coder = {}
Post.new.encode_with(coder)
coder # => {"attributes" => {"id" => nil, ... }}

📝 Source code

# File activerecord/lib/active_record/core.rb, line 565
    def encode_with(coder)
      self.class.yaml_encoder.encode(@attributes, coder)
      coder["new_record"] = new_record?
      coder["active_record_yaml_version"] = 2
    end

🔎 See on GitHub

eql?(comparison_object)

Alias for: ==

freeze()

Clone and freeze the attributes hash such that associations are still accessible, even on destroyed records, but cloned models will not be frozen.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 603
    def freeze
      @attributes = @attributes.clone.freeze
      self
    end

🔎 See on GitHub

frozen?()

Returns true if the attributes hash has been frozen.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 609
    def frozen?
      @attributes.frozen?
    end

🔎 See on GitHub

hash()

Delegates to id in order to allow two records of the same type and id to work with something like:

[ Person.find(1), Person.find(2), Person.find(3) ] & [ Person.find(1), Person.find(4) ] # => [ Person.find(1) ]

📝 Source code

# File activerecord/lib/active_record/core.rb, line 590
    def hash
      id = self.id

      if id
        self.class.hash ^ id.hash
      else
        super
      end
    end

🔎 See on GitHub

init_with(coder, &block)

Initialize an empty model object from coder. coder should be the result of previously encoding an Active Record model, using encode_with.

class Post < ActiveRecord::Base
end

old_post = Post.new(title: "hello world")
coder = {}
old_post.encode_with(coder)

post = Post.allocate
post.init_with(coder)
post.title # => 'hello world'

📝 Source code

# File activerecord/lib/active_record/core.rb, line 488
    def init_with(coder, &block)
      coder = LegacyYamlAdapter.convert(coder)
      attributes = self.class.yaml_encoder.decode(coder)
      init_with_attributes(attributes, coder["new_record"], &block)
    end

🔎 See on GitHub

inspect()

Returns the contents of the record as a nicely formatted string.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 687
    def inspect
      # We check defined?(@attributes) not to issue warnings if the object is
      # allocated but not initialized.
      inspection = if defined?(@attributes) && @attributes
        self.class.attribute_names.filter_map do |name|
          if _has_attribute?(name)
            "#{name}: #{attribute_for_inspect(name)}"
          end
        end.join(", ")
      else
        "not initialized"
      end

      "#<#{self.class} #{inspection}>"
    end

🔎 See on GitHub

pretty_print(pp)

Takes a PP and prettily prints this record to it, allowing you to get a nice result from pp record when pp is required.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 705
    def pretty_print(pp)
      return super if custom_inspect_method_defined?
      pp.object_address_group(self) do
        if defined?(@attributes) && @attributes
          attr_names = self.class.attribute_names.select { |name| _has_attribute?(name) }
          pp.seplist(attr_names, proc { pp.text "," }) do |attr_name|
            pp.breakable " "
            pp.group(1) do
              pp.text attr_name
              pp.text ":"
              pp.breakable
              value = _read_attribute(attr_name)
              value = inspection_filter.filter_param(attr_name, value) unless value.nil?
              pp.pp value
            end
          end
        else
          pp.breakable " "
          pp.text "not initialized"
        end
      end
    end

🔎 See on GitHub

readonly!()

Marks this record as read only.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 678
    def readonly!
      @readonly = true
    end

🔎 See on GitHub

readonly?()

Returns true if the record is read only.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 631
    def readonly?
      @readonly
    end

🔎 See on GitHub

slice(*methods)

Returns a hash of the given methods with their names as keys and returned values as values.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 729
    def slice(*methods)
      methods.flatten.index_with { |method| public_send(method) }.with_indifferent_access
    end

🔎 See on GitHub

strict_loading!(value = true, mode: :all)

Sets the record to strict_loading mode. This will raise an error if the record tries to lazily load an association.

user = User.first
user.strict_loading! # => true
user.comments
=> ActiveRecord::StrictLoadingViolationError

Parameters:

value - Boolean specifying whether to enable or disable strict loading.

mode - Symbol specifying strict loading mode. Defaults to :all. Using

:n_plus_one_only mode will only raise an error if an association
that will lead to an n plus one query is lazily loaded.

Example:

user = User.first
user.strict_loading!(false) # => false
user.comments
=> #<ActiveRecord::Associations::CollectionProxy>

📝 Source code

# File activerecord/lib/active_record/core.rb, line 661
    def strict_loading!(value = true, mode: :all)
      unless [:all, :n_plus_one_only].include?(mode)
        raise ArgumentError, "The :mode option must be one of [:all, :n_plus_one_only]."
      end

      @strict_loading_mode = mode
      @strict_loading = value
    end

🔎 See on GitHub

strict_loading?()

Returns true if the record is in strict_loading mode.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 636
    def strict_loading?
      @strict_loading
    end

🔎 See on GitHub

strict_loading_n_plus_one_only?()

Returns true if the record uses strict_loading with :n_plus_one_only mode enabled.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 673
    def strict_loading_n_plus_one_only?
      @strict_loading_mode == :n_plus_one_only
    end

🔎 See on GitHub

values_at(*methods)

Returns an array of the values returned by the given methods.

📝 Source code

# File activerecord/lib/active_record/core.rb, line 734
    def values_at(*methods)
      methods.flatten.map! { |method| public_send(method) }
    end

🔎 See on GitHub

ActiveRecord::Core

Namespace

Module

Class

Methods

Attributes

Class Public methods

configurations()

configurations=(config)

connection_handler()

connection_handler=(handler)

connection_handlers()

connection_handlers=(handlers)

current_preventing_writes()

current_role()

current_shard()

destroy_association_async_job

enumerate_columns_in_select_statements

logger

new(attributes = nil)

Example:

Instance Public methods

<=>(other_object)

==(comparison_object)

clone

connection_handler()

dup

encode_with(coder)

eql?(comparison_object)

freeze()

frozen?()

hash()

init_with(coder, &block)

inspect()

pretty_print(pp)

readonly!()

readonly?()

slice(*methods)

strict_loading!(value = true, mode: :all)

Parameters:

Example:

strict_loading?()

strict_loading_n_plus_one_only?()

values_at(*methods)