Module: ActiveRecord::AttributeMethods::PrimaryKey::ClassMethods

Defined in:
activerecord/lib/active_record/attribute_methods/primary_key.rb

Constant Summary collapse

ID_ATTRIBUTE_METHODS =
%w(id id= id? id_before_type_cast id_was id_in_database).to_set

Instance Method Summary collapse

Instance Method Details

#dangerous_attribute_method?(method_name) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 63

def dangerous_attribute_method?(method_name)
  super && !ID_ATTRIBUTE_METHODS.include?(method_name)
end

#get_primary_key(base_name) ⇒ Object

:nodoc:


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# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 89

def get_primary_key(base_name) #:nodoc:
  if base_name && primary_key_prefix_type == :table_name
    base_name.foreign_key(false)
  elsif base_name && primary_key_prefix_type == :table_name_with_underscore
    base_name.foreign_key
  else
    if ActiveRecord::Base != self && table_exists?
      pk = connection.schema_cache.primary_keys(table_name)
      suppress_composite_primary_key(pk)
    else
      "id"
    end
  end
end

#instance_method_already_implemented?(method_name) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 59

def instance_method_already_implemented?(method_name)
  super || primary_key && ID_ATTRIBUTE_METHODS.include?(method_name)
end

#primary_keyObject

Defines the primary key field – can be overridden in subclasses. Overwriting will negate any effect of the primary_key_prefix_type setting, though.


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# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 70

def primary_key
  @primary_key = reset_primary_key unless defined? @primary_key
  @primary_key
end

#primary_key=(value) ⇒ Object

Sets the name of the primary key column.

class Project < ActiveRecord::Base
  self.primary_key = 'sysid'
end

You can also define the #primary_key method yourself:

class Project < ActiveRecord::Base
  def self.primary_key
    'foo_' + super
  end
end

Project.primary_key # => "foo_id"

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# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 119

def primary_key=(value)
  @primary_key        = value && -value.to_s
  @quoted_primary_key = nil
  @attributes_builder = nil
end

#quoted_primary_keyObject

Returns a quoted version of the primary key name, used to construct SQL statements.


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# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 77

def quoted_primary_key
  @quoted_primary_key ||= connection.quote_column_name(primary_key)
end

#reset_primary_keyObject

:nodoc:


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# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 81

def reset_primary_key #:nodoc:
  if base_class?
    self.primary_key = get_primary_key(base_class.name)
  else
    self.primary_key = base_class.primary_key
  end
end