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).to_set

Instance Method Summary collapse

Instance Method Details

#dangerous_attribute_method?(method_name) ⇒ Boolean

Returns:

  • (Boolean)

65
66
67
# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 65

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

#define_method_attribute(attr_name) ⇒ Object


55
56
57
58
59
60
61
# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 55

def define_method_attribute(attr_name)
  super

  if attr_name == primary_key && attr_name != 'id'
    generated_attribute_methods.send(:alias_method, :id, primary_key)
  end
end

#get_primary_key(base_name) ⇒ Object

:nodoc:


91
92
93
94
95
96
97
98
99
100
101
102
103
# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 91

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?
      connection.schema_cache.primary_keys(table_name)
    else
      'id'
    end
  end
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.


72
73
74
75
# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 72

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"

120
121
122
123
124
# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 120

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.


79
80
81
# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 79

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

#reset_primary_keyObject

:nodoc:


83
84
85
86
87
88
89
# File 'activerecord/lib/active_record/attribute_methods/primary_key.rb', line 83

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