Module: ActiveRecord::Core

Extended by:
ActiveSupport::Concern
Included in:
Base
Defined in:
activerecord/lib/active_record/core.rb

Defined Under Namespace

Modules: ClassMethods

Instance Method Summary collapse

Methods included from ActiveSupport::Concern

append_features, extended, included

Instance Method Details

#<=>(other_object) ⇒ Object

Allows sort on objects


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# File 'activerecord/lib/active_record/core.rb', line 311

def <=>(other_object)
  if other_object.is_a?(self.class)
    self.to_key <=> other_object.to_key
  end
end

#==(comparison_object) ⇒ Object Also known as: eql?

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.


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# File 'activerecord/lib/active_record/core.rb', line 283

def ==(comparison_object)
  super ||
    comparison_object.instance_of?(self.class) &&
    id.present? &&
    comparison_object.id == id
end

#connection_handlerObject


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# File 'activerecord/lib/active_record/core.rb', line 328

def connection_handler
  self.class.connection_handler
end

#encode_with(coder) ⇒ Object

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, ... }}

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# File 'activerecord/lib/active_record/core.rb', line 270

def encode_with(coder)
  coder['attributes'] = attributes
end

#freezeObject

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


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# File 'activerecord/lib/active_record/core.rb', line 300

def freeze
  @attributes = @attributes.clone.freeze
  self
end

#frozen?Boolean

Returns true if the attributes hash has been frozen.

Returns:

  • (Boolean)

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# File 'activerecord/lib/active_record/core.rb', line 306

def frozen?
  @attributes.frozen?
end

#has_transactional_callbacks?Boolean

:nodoc:

Returns:

  • (Boolean)

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# File 'activerecord/lib/active_record/core.rb', line 357

def has_transactional_callbacks? # :nodoc:
  !_rollback_callbacks.empty? || !_commit_callbacks.empty? || !_create_callbacks.empty?
end

#hashObject

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) ]

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# File 'activerecord/lib/active_record/core.rb', line 293

def hash
  id.hash
end

#init_with(coder) ⇒ Object

Initialize an empty model object from coder. coder must contain the attributes necessary for initializing an empty model object. For example:

class Post < ActiveRecord::Base
end

post = Post.allocate
post.init_with('attributes' => { 'title' => 'hello world' })
post.title # => 'hello world'

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# File 'activerecord/lib/active_record/core.rb', line 195

def init_with(coder)
  @attributes   = self.class.initialize_attributes(coder['attributes'])
  @columns_hash = self.class.column_types.merge(coder['column_types'] || {})

  init_internals

  @new_record = false

  run_callbacks :find
  run_callbacks :initialize

  self
end

#initialize(attributes = nil) {|_self| ... } ⇒ Object

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')

Yields:

  • (_self)

Yield Parameters:


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# File 'activerecord/lib/active_record/core.rb', line 167

def initialize(attributes = nil)
  defaults = self.class.column_defaults.dup
  defaults.each { |k, v| defaults[k] = v.dup if v.duplicable? }

  @attributes   = self.class.initialize_attributes(defaults)
  @columns_hash = self.class.column_types.dup

  init_internals
  init_changed_attributes
  ensure_proper_type
  populate_with_current_scope_attributes

  assign_attributes(attributes) if attributes

  yield self if block_given?
  run_callbacks :initialize unless _initialize_callbacks.empty?
end

#initialize_dup(other) ⇒ Object

:nodoc:


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# File 'activerecord/lib/active_record/core.rb', line 236

def initialize_dup(other) # :nodoc:
  cloned_attributes = other.clone_attributes(:read_attribute_before_type_cast)
  self.class.initialize_attributes(cloned_attributes, :serialized => false)

  @attributes = cloned_attributes
  @attributes[self.class.primary_key] = nil

  run_callbacks(:initialize) unless _initialize_callbacks.empty?

  @changed_attributes = {}
  init_changed_attributes

  @aggregation_cache = {}
  @association_cache = {}
  @attributes_cache  = {}

  @new_record  = true

  ensure_proper_type
  super
end

#inspectObject

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


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# File 'activerecord/lib/active_record/core.rb', line 333

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.column_names.collect { |name|
                   if has_attribute?(name)
                     "#{name}: #{attribute_for_inspect(name)}"
                   end
                 }.compact.join(", ")
               else
                 "not initialized"
               end
  "#<#{self.class} #{inspection}>"
end

#readonly!Object

Marks this record as read only.


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# File 'activerecord/lib/active_record/core.rb', line 324

def readonly!
  @readonly = true
end

#readonly?Boolean

Returns true if the record is read only. Records loaded through joins with piggy-back attributes will be marked as read only since they cannot be saved.

Returns:

  • (Boolean)

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# File 'activerecord/lib/active_record/core.rb', line 319

def readonly?
  @readonly
end

#set_transaction_state(state) ⇒ Object

:nodoc:


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# File 'activerecord/lib/active_record/core.rb', line 353

def set_transaction_state(state) # :nodoc:
  @transaction_state = state
end

#slice(*methods) ⇒ Object

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


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# File 'activerecord/lib/active_record/core.rb', line 349

def slice(*methods)
  Hash[methods.map { |method| [method, public_send(method)] }].with_indifferent_access
end