module Sequel::Model::Associations::ClassMethods
Each kind of association adds a number of instance methods to the model class which are specialized according to the association type and optional parameters given in the definition. Example:
class Project < Sequel::Model many_to_one :portfolio # or: one_to_one :portfolio one_to_many :milestones # or: many_to_many :milestones end
The project class now has the following instance methods:
- portfolio
-
Returns the associated portfolio.
- portfolio=(obj)
-
Sets the associated portfolio to the object, but the change is not persisted until you save the record (for
many_to_one
associations). - portfolio_dataset
-
Returns a dataset that would return the associated portfolio, only useful in fairly specific circumstances.
- milestones
-
Returns an array of associated milestones
- add_milestone(obj)
-
Associates the passed milestone with this object.
- remove_milestone(obj)
-
Removes the association with the passed milestone.
- remove_all_milestones
-
Removes associations with all associated milestones.
- milestones_dataset
-
Returns a dataset that would return the associated milestones, allowing for further filtering/limiting/etc.
If you want to override the behavior of the add_/remove_/remove_all_/ methods or the association setter method, use the :adder, :remover, :clearer, and/or :setter options. These options override the default behavior.
By default the classes for the associations are inferred from the association name, so for example the Project#portfolio will return an instance of Portfolio, and Project#milestones will return an array of Milestone instances. You can use the :class option to change which class is used.
Association definitions are also reflected by the class, e.g.:
Project.associations => [:portfolio, :milestones] Project.association_reflection(:portfolio) => #<Sequel::Model::Associations::ManyToOneAssociationReflection Project.many_to_one :portfolio>
Associations
should not have the same names as any of the columns in the model's current table they reference. If you are dealing with an existing schema that has a column named status, you can't name the association status, you'd have to name it foo_status or something else. If you give an association the same name as a column, you will probably end up with an association that doesn't work, or a SystemStackError.
For a more in depth general overview, as well as a reference guide, see the Association Basics guide. For examples of advanced usage, see the Advanced Associations guide.
Attributes
All association reflections defined for this model (default: {}).
Hash
with column symbol keys and arrays of many_to_one
association symbols that should be cleared when the column value changes.
Whether association metadata should be cached in the association reflection. If not cached, it will be computed on demand. In general you only want to set this to false when using code reloading. When using code reloading, setting this will make sure that if an associated class is removed or modified, this class will not have a reference to the previous class.
The default options to use for all associations. This hash is merged into the association reflection hash for all association reflections.
The default options to use for all associations of a given type. This is a hash keyed by association type symbol. If there is a value for the association type symbol key, the resulting hash will be merged into the association reflection hash for all association reflections of that type.
The default :eager_limit_strategy option to use for limited or offset associations (default: true, causing Sequel
to use what it considers the most appropriate strategy).
Public Instance Methods
Array
of all association reflections for this model class
# File lib/sequel/model/associations.rb 1595 def all_association_reflections 1596 association_reflections.values 1597 end
Associates a related model with the current model. The following types are supported:
- :many_to_one
-
Foreign key in current model's table points to associated model's primary key. Each associated model object can be associated with more than one current model objects. Each current model object can be associated with only one associated model object.
- :one_to_many
-
Foreign key in associated model's table points to this model's primary key. Each current model object can be associated with more than one associated model objects. Each associated model object can be associated with only one current model object.
- :one_through_one
-
Similar to
many_to_many
in terms of foreign keys, but only one object is associated to the current object through the association. Provides only getter methods, no setter or modification methods. - :one_to_one
-
Similar to
one_to_many
in terms of foreign keys, but only one object is associated to the current object through the association. The methods created are similar tomany_to_one
, except that theone_to_one
setter method saves the passed object. - :many_to_many
-
A join table is used that has a foreign key that points to this model's primary key and a foreign key that points to the associated model's primary key. Each current model object can be associated with many associated model objects, and each associated model object can be associated with many current model objects.
The following options can be supplied:
Multiple Types¶ ↑
- :adder
-
Proc used to define the private add* method for doing the database work to associate the given object to the current object (*_to_many assocations). Set to nil to not define a add_* method for the association.
- :after_add
-
Symbol
, Proc, or array of both/either specifying a callback to call after a new item is added to the association. - :after_load
-
Symbol
, Proc, or array of both/either specifying a callback to call after the associated record(s) have been retrieved from the database. - :after_remove
-
Symbol
, Proc, or array of both/either specifying a callback to call after an item is removed from the association. - :after_set
-
Symbol
, Proc, or array of both/either specifying a callback to call after an item is set using the association setter method. - :allow_eager
-
If set to false, you cannot load the association eagerly via eager or eager_graph
- :allow_eager_graph
-
If set to false, you cannot load the association eagerly via eager_graph.
- :allow_filtering_by
-
If set to false, you cannot use the association when filtering
- :before_add
-
Symbol
, Proc, or array of both/either specifying a callback to call before a new item is added to the association. - :before_remove
-
Symbol
, Proc, or array of both/either specifying a callback to call before an item is removed from the association. - :before_set
-
Symbol
, Proc, or array of both/either specifying a callback to call before an item is set using the association setter method. - :cartesian_product_number
-
the number of joins completed by this association that could cause more than one row for each row in the current table (default: 0 for
many_to_one
,one_to_one
, andone_through_one
associations, 1 forone_to_many
andmany_to_many
associations). - :class
-
The associated class or its name as a string or symbol. If not given, uses the association's name, which is camelized (and singularized unless the type is :many_to_one, :one_to_one, or
one_through_one
). If this is specified as a string or symbol, you must specify the full class name (e.g. “::SomeModule::MyModel”). - :class_namespace
-
If :class is given as a string or symbol, sets the default namespace in which to look for the class.
class: 'Foo', class_namespace: 'Bar'
looks for::Bar::Foo
.) - :clearer
-
Proc used to define the private remove_all* method for doing the database work to remove all objects associated to the current object (*_to_many assocations). Set to nil to not define a remove_all_* method for the association.
- :clone
-
Merge the current options and block into the options and block used in defining the given association. Can be used to DRY up a bunch of similar associations that all share the same options such as :class and :key, while changing the order and block used.
- :conditions
-
The conditions to use to filter the association, can be any argument passed to where. This option is not respected when using eager_graph or association_join, unless it is hash or array of two element arrays. Consider also specifying the :graph_block option if the value for this option is not a hash or array of two element arrays and you plan to use this association in eager_graph or association_join.
- :dataset
-
A proc that is used to define the method to get the base dataset to use (before the other options are applied). If the proc accepts an argument, it is passed the related association reflection. It is a best practice to always have the dataset accept an argument and use the argument to return the appropriate dataset.
- :distinct
-
Use the DISTINCT clause when selecting associating object, both when lazy loading and eager loading via .eager (but not when using .eager_graph).
- :eager
-
The associations to eagerly load via
eager
when loading the associated object(s). - :eager_block
-
If given, use the block instead of the default block when eagerly loading. To not use a block when eager loading (when one is used normally), set to nil.
- :eager_graph
-
The associations to eagerly load via
eager_graph
when loading the associated object(s).many_to_many
associations with this option cannot be eagerly loaded viaeager
. - :eager_grapher
-
A proc to use to implement eager loading via
eager_graph
, overriding the default. Takes an options hash with at least the entries :self (the receiver of the eager_graph call), :table_alias (the alias to use for table to graph into the association), and :implicit_qualifier (the alias that was used for the current table). Should return a copy of the dataset with the association graphed into it. - :eager_limit_strategy
-
Determines the strategy used for enforcing limits and offsets when eager loading associations via the
eager
method. - :eager_loader
-
A proc to use to implement eager loading, overriding the default. Takes a single hash argument, with at least the keys: :rows, which is an array of current model instances, :associations, which is a hash of dependent associations, :self, which is the dataset doing the eager loading, :eager_block, which is a dynamic callback that should be called with the dataset, and :id_map, which is a mapping of key values to arrays of current model instances. In the proc, the associated records should be queried from the database and the associations cache for each record should be populated.
- :eager_loader_key
-
A symbol for the key column to use to populate the key_hash for the eager loader. Can be set to nil to not populate the key_hash.
- :extend
-
A module or array of modules to extend the dataset with.
- :filter_limit_strategy
-
Determines the strategy used for enforcing limits and offsets when filtering by limited associations. Possible options are :window_function, :distinct_on, or :correlated_subquery depending on association type and database type.
- :graph_alias_base
-
The base name to use for the table alias when eager graphing. Defaults to the name of the association. If the alias name has already been used in the query,
Sequel
will create a unique alias by appending a numeric suffix (e.g. alias_0, alias_1, …) until the alias is unique. - :graph_block
-
The block to pass to join_table when eagerly loading the association via
eager_graph
. - :graph_conditions
-
The additional conditions to use on the
SQL
join when eagerly loading the association viaeager_graph
. Should be a hash or an array of two element arrays. If not specified, the :conditions option is used if it is a hash or array of two element arrays. - :graph_join_type
-
The type of
SQL
join to use when eagerly loading the association via eager_graph. Defaults to :left_outer. - :graph_only_conditions
-
The conditions to use on the
SQL
join when eagerly loading the association viaeager_graph
, instead of the default conditions specified by the foreign/primary keys. This option causes the :graph_conditions option to be ignored. - :graph_order
-
the order to use when using eager_graph, instead of the default order. This should be used in the case where :order contains an identifier qualified by the table's name, which may not match the alias used when eager graphing. By setting this to the unqualified identifier, it will be automatically qualified when using eager_graph.
- :graph_select
-
A column or array of columns to select from the associated table when eagerly loading the association via
eager_graph
. Defaults to all columns in the associated table. - :limit
-
Limit the number of records to the provided value. Use an array with two elements for the value to specify a limit (first element) and an offset (second element).
- :methods_module
-
The module that methods the association creates will be placed into. Defaults to the module containing the model's columns.
- :no_association_method
-
Do not add a method for the association. This can save memory if the association method is never used.
- :no_dataset_method
-
Do not add a method for the association dataset. This can save memory if the dataset method is never used.
- :order
-
the column(s) by which to order the association dataset. Can be a singular column symbol or an array of column symbols.
- :order_eager_graph
-
Whether to add the association's order to the graphed dataset's order when graphing via
eager_graph
. Defaults to true, so set to false to disable. - :read_only
-
Do not add a setter method (for
many_to_one
orone_to_one
associations), or add_/remove_/remove_all_ methods (forone_to_many
andmany_to_many
associations). - :reciprocal
-
the symbol name of the reciprocal association, if it exists. By default,
Sequel
will try to determine it by looking at the associated model's assocations for a association that matches the current association's key(s). Set to nil to not use a reciprocal. - :remover
-
Proc used to define the private remove* method for doing the database work to remove the association between the given object and the current object (*_to_many assocations). Set to nil to not define a remove_* method for the association.
- :select
-
the columns to select. Defaults to the associated class's table_name.* in an association that uses joins, which means it doesn't include the attributes from the join table. If you want to include the join table attributes, you can use this option, but beware that the join table attributes can clash with attributes from the model table, so you should alias any attributes that have the same name in both the join table and the associated table.
- :setter
-
Proc used to define the private _*= method for doing the work to setup the assocation between the given object and the current object (*_to_one associations). Set to nil to not define a setter method for the association.
- :subqueries_per_union
-
The number of subqueries to use in each UNION query, for eager loading limited associations using the default :union strategy.
- :validate
-
Set to false to not validate when implicitly saving any associated object.
:many_to_one¶ ↑
- :key
-
foreign key in current model's table that references associated model's primary key, as a symbol. Defaults to :“#{name}_id”. Can use an array of symbols for a composite key association.
- :key_column
-
Similar to, and usually identical to, :key, but :key refers to the model method to call, where :key_column refers to the underlying column. Should only be used if the model method differs from the foreign key column, in conjunction with defining a model alias method for the key column.
- :primary_key
-
column in the associated table that :key option references, as a symbol. Defaults to the primary key of the associated table. Can use an array of symbols for a composite key association.
- :primary_key_method
-
the method symbol or array of method symbols to call on the associated object to get the foreign key values. Defaults to :primary_key option.
- :qualify
-
Whether to use qualified primary keys when loading the association. The default is true, so you must set to false to not qualify. Qualification rarely causes problems, but it's necessary to disable in some cases, such as when you are doing a JOIN USING operation on the column on
Oracle
.
:one_to_many and :one_to_one¶ ↑
- :key
-
foreign key in associated model's table that references current model's primary key, as a symbol. Defaults to :“#{self.name.underscore}_id”. Can use an array of symbols for a composite key association.
- :key_method
-
the method symbol or array of method symbols to call on the associated object to get the foreign key values. Defaults to :key option.
- :primary_key
-
column in the current table that :key option references, as a symbol. Defaults to primary key of the current table. Can use an array of symbols for a composite key association.
- :primary_key_column
-
Similar to, and usually identical to, :primary_key, but :primary_key refers to the model method call, where :primary_key_column refers to the underlying column. Should only be used if the model method differs from the primary key column, in conjunction with defining a model alias method for the primary key column.
- :raise_on_save_failure
-
Do not raise exceptions for hook or validation failures when saving associated objects in the add/remove methods (return nil instead) [one_to_many only].
:many_to_many and :one_through_one¶ ↑
- :graph_join_table_block
-
The block to pass to
join_table
for the join table when eagerly loading the association viaeager_graph
. - :graph_join_table_conditions
-
The additional conditions to use on the
SQL
join for the join table when eagerly loading the association viaeager_graph
. Should be a hash or an array of two element arrays. - :graph_join_table_join_type
-
The type of
SQL
join to use for the join table when eagerly loading the association viaeager_graph
. Defaults to the :graph_join_type option or :left_outer. - :graph_join_table_only_conditions
-
The conditions to use on the
SQL
join for the join table when eagerly loading the association viaeager_graph
, instead of the default conditions specified by the foreign/primary keys. This option causes the :graph_join_table_conditions option to be ignored. - :join_table
-
name of table that includes the foreign keys to both the current model and the associated model, as a symbol. Defaults to the name of current model and name of associated model, pluralized, underscored, sorted, and joined with '_'.
- :join_table_block
-
proc that can be used to modify the dataset used in the add/remove/remove_all methods. Should accept a dataset argument and return a modified dataset if present.
- :join_table_db
-
When retrieving records when using lazy loading or eager loading via
eager
, instead of a join between to the join table and the associated table, use a separate query for the join table using the givenDatabase
object. - :left_key
-
foreign key in join table that points to current model's primary key, as a symbol. Defaults to :“#{self.name.underscore}_id”. Can use an array of symbols for a composite key association.
- :left_primary_key
-
column in current table that :left_key points to, as a symbol. Defaults to primary key of current table. Can use an array of symbols for a composite key association.
- :left_primary_key_column
-
Similar to, and usually identical to, :left_primary_key, but :left_primary_key refers to the model method to call, where :left_primary_key_column refers to the underlying column. Should only be used if the model method differs from the left primary key column, in conjunction with defining a model alias method for the left primary key column.
- :right_key
-
foreign key in join table that points to associated model's primary key, as a symbol. Defaults to :“#{name.to_s.singularize}_id”. Can use an array of symbols for a composite key association.
- :right_primary_key
-
column in associated table that :right_key points to, as a symbol. Defaults to primary key of the associated table. Can use an array of symbols for a composite key association.
- :right_primary_key_method
-
the method symbol or array of method symbols to call on the associated object to get the foreign key values for the join table. Defaults to :right_primary_key option.
- :uniq
-
Adds a after_load callback that makes the array of objects unique.
# File lib/sequel/model/associations.rb 1830 def associate(type, name, opts = OPTS, &block) 1831 raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]} 1832 raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol) 1833 1834 # dup early so we don't modify opts 1835 orig_opts = opts.dup 1836 1837 if opts[:clone] 1838 cloned_assoc = association_reflection(opts[:clone]) 1839 remove_class_name = orig_opts[:class] && !orig_opts[:class_name] 1840 orig_opts = cloned_assoc[:orig_opts].merge(orig_opts) 1841 orig_opts.delete(:class_name) if remove_class_name 1842 end 1843 1844 opts = Hash[default_association_options] 1845 if type_options = default_association_type_options[type] 1846 opts.merge!(type_options) 1847 end 1848 opts.merge!(orig_opts) 1849 opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self) 1850 1851 opts[:block] = block if block 1852 opts[:instance_specific] = true if orig_opts[:dataset] 1853 if !opts.has_key?(:instance_specific) && (block || orig_opts[:block]) 1854 # It's possible the association is instance specific, in that it depends on 1855 # values other than the foreign key value. This needs to be checked for 1856 # in certain places to disable optimizations. 1857 opts[:instance_specific] = _association_instance_specific_default(name) 1858 end 1859 opts = assoc_class.new.merge!(opts) 1860 1861 if opts[:clone] && !opts.cloneable?(cloned_assoc) 1862 raise(Error, "cannot clone an association to an association of different type (association #{name} with type #{type} cloning #{opts[:clone]} with type #{cloned_assoc[:type]})") 1863 end 1864 1865 opts[:use_placeholder_loader] = !opts[:instance_specific] && !opts[:eager_graph] 1866 opts[:eager_block] = opts[:block] unless opts.include?(:eager_block) 1867 opts[:graph_join_type] ||= :left_outer 1868 opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph) 1869 conds = opts[:conditions] 1870 opts[:graph_alias_base] ||= name 1871 opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds) 1872 opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a 1873 opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select] 1874 [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type| 1875 opts[cb_type] = Array(opts[cb_type]) if opts[cb_type] 1876 end 1877 1878 if opts[:extend] 1879 opts[:extend] = Array(opts[:extend]) 1880 opts[:reverse_extend] = opts[:extend].reverse 1881 end 1882 1883 late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name) 1884 1885 # Remove :class entry if it exists and is nil, to work with cached_fetch 1886 opts.delete(:class) unless opts[:class] 1887 1888 def_association(opts) 1889 1890 orig_opts.delete(:clone) 1891 opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name] 1892 orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block]) 1893 opts[:orig_opts] = orig_opts 1894 # don't add to association_reflections until we are sure there are no errors 1895 association_reflections[name] = opts 1896 end
The association reflection hash for the association of the given name.
# File lib/sequel/model/associations.rb 1899 def association_reflection(name) 1900 association_reflections[name] 1901 end
Array
of association name symbols
# File lib/sequel/model/associations.rb 1904 def associations 1905 association_reflections.keys 1906 end
Eager load the association with the given eager loader options.
# File lib/sequel/model/associations.rb 1909 def eager_load_results(opts, eo, &block) 1910 opts.eager_load_results(eo, &block) 1911 end
Finalize all associations such that values that are looked up dynamically in associated classes are set statically. As this modifies the associations, it must be done before calling freeze.
# File lib/sequel/model/associations.rb 1928 def finalize_associations 1929 @association_reflections.each_value(&:finalize) 1930 end
Freeze association related metadata when freezing model class.
# File lib/sequel/model/associations.rb 1914 def freeze 1915 @association_reflections.freeze.each_value(&:freeze) 1916 @autoreloading_associations.freeze.each_value(&:freeze) 1917 @default_association_options.freeze 1918 @default_association_type_options.freeze 1919 @default_association_type_options.each_value(&:freeze) 1920 1921 super 1922 end
Shortcut for adding a many_to_many
association, see associate
# File lib/sequel/model/associations.rb 1933 def many_to_many(name, opts=OPTS, &block) 1934 associate(:many_to_many, name, opts, &block) 1935 end
Shortcut for adding a many_to_one
association, see associate
# File lib/sequel/model/associations.rb 1938 def many_to_one(name, opts=OPTS, &block) 1939 associate(:many_to_one, name, opts, &block) 1940 end
Shortcut for adding a one_through_one
association, see associate
# File lib/sequel/model/associations.rb 1943 def one_through_one(name, opts=OPTS, &block) 1944 associate(:one_through_one, name, opts, &block) 1945 end
Shortcut for adding a one_to_many
association, see associate
# File lib/sequel/model/associations.rb 1948 def one_to_many(name, opts=OPTS, &block) 1949 associate(:one_to_many, name, opts, &block) 1950 end
Shortcut for adding a one_to_one
association, see associate
# File lib/sequel/model/associations.rb 1953 def one_to_one(name, opts=OPTS, &block) 1954 associate(:one_to_one, name, opts, &block) 1955 end
Private Instance Methods
The default value for the instance_specific option, if the association could be instance specific and the :instance_specific option is not specified.
# File lib/sequel/model/associations.rb 1964 def _association_instance_specific_default(_) 1965 true 1966 end
The module to use for the association's methods. Defaults to the overridable_methods_module.
# File lib/sequel/model/associations.rb 1970 def association_module(opts=OPTS) 1971 opts.fetch(:methods_module, overridable_methods_module) 1972 end
Add a method to the module included in the class, so the method can be easily overridden in the class itself while allowing for super to be called.
# File lib/sequel/model/associations.rb 1977 def association_module_def(name, opts=OPTS, &block) 1978 mod = association_module(opts) 1979 mod.send(:define_method, name, &block) 1980 mod.send(:alias_method, name, name) 1981 end
Add a method to the module included in the class, so the method can be easily overridden in the class itself while allowing for super to be called. This method allows passing keywords through the defined methods.
# File lib/sequel/model/associations.rb 1987 def association_module_delegate_def(name, opts, &block) 1988 mod = association_module(opts) 1989 mod.send(:define_method, name, &block) 1990 # :nocov: 1991 mod.send(:ruby2_keywords, name) if mod.respond_to?(:ruby2_keywords, true) 1992 # :nocov: 1993 mod.send(:alias_method, name, name) 1994 end
Add a private method to the module included in the class.
# File lib/sequel/model/associations.rb 1997 def association_module_private_def(name, opts=OPTS, &block) 1998 association_module_def(name, opts, &block) 1999 association_module(opts).send(:private, name) 2000 end
Delegate to the type-specific association method to setup the association, and define the association instance methods.
# File lib/sequel/model/associations.rb 2004 def def_association(opts) 2005 send(:"def_#{opts[:type]}", opts) 2006 def_association_instance_methods(opts) 2007 end
Define all of the association instance methods for this association.
# File lib/sequel/model/associations.rb 2017 def def_association_instance_methods(opts) 2018 # Always set the method names in the association reflection, even if they 2019 # are not used, for backwards compatibility. 2020 opts[:dataset_method] = :"#{opts[:name]}_dataset" 2021 if opts.returns_array? 2022 sname = singularize(opts[:name]) 2023 opts[:_add_method] = :"_add_#{sname}" 2024 opts[:add_method] = :"add_#{sname}" 2025 opts[:_remove_method] = :"_remove_#{sname}" 2026 opts[:remove_method] = :"remove_#{sname}" 2027 opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}" 2028 opts[:remove_all_method] = :"remove_all_#{opts[:name]}" 2029 else 2030 opts[:_setter_method] = :"_#{opts[:name]}=" 2031 opts[:setter_method] = :"#{opts[:name]}=" 2032 end 2033 2034 association_module_def(opts.dataset_method, opts){_dataset(opts)} unless opts[:no_dataset_method] 2035 if opts[:block] 2036 opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block]) 2037 end 2038 opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1 2039 opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset]) 2040 def_association_method(opts) unless opts[:no_association_method] 2041 2042 return if opts[:read_only] 2043 2044 if opts[:setter] && opts[:_setter] 2045 # This is backwards due to backwards compatibility 2046 association_module_private_def(opts[:_setter_method], opts, &opts[:setter]) 2047 association_module_def(opts[:setter_method], opts, &opts[:_setter]) 2048 end 2049 2050 if adder = opts[:adder] 2051 association_module_private_def(opts[:_add_method], opts, &adder) 2052 association_module_delegate_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)} 2053 end 2054 2055 if remover = opts[:remover] 2056 association_module_private_def(opts[:_remove_method], opts, &remover) 2057 association_module_delegate_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)} 2058 end 2059 2060 if clearer = opts[:clearer] 2061 association_module_private_def(opts[:_remove_all_method], opts, &clearer) 2062 association_module_delegate_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)} 2063 end 2064 end
Adds the association method to the association methods module.
# File lib/sequel/model/associations.rb 2010 def def_association_method(opts) 2011 association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block| 2012 load_associated_objects(opts, dynamic_opts, &block) 2013 end 2014 end
Configures many_to_many
and one_through_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2067 def def_many_to_many(opts) 2068 one_through_one = opts[:type] == :one_through_one 2069 left = (opts[:left_key] ||= opts.default_left_key) 2070 lcks = opts[:left_keys] = Array(left) 2071 right = (opts[:right_key] ||= opts.default_right_key) 2072 rcks = opts[:right_keys] = Array(right) 2073 left_pk = (opts[:left_primary_key] ||= self.primary_key) 2074 opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key) 2075 lcpks = opts[:left_primary_keys] = Array(left_pk) 2076 lpkc = opts[:left_primary_key_column] ||= left_pk 2077 lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc) 2078 raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length 2079 if opts[:right_primary_key] 2080 rcpks = Array(opts[:right_primary_key]) 2081 raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length 2082 end 2083 opts[:uses_left_composite_keys] = lcks.length > 1 2084 uses_rcks = opts[:uses_right_composite_keys] = rcks.length > 1 2085 opts[:cartesian_product_number] ||= one_through_one ? 0 : 1 2086 join_table = (opts[:join_table] ||= opts.default_join_table) 2087 opts[:left_key_alias] ||= opts.default_associated_key_alias 2088 opts[:graph_join_table_join_type] ||= opts[:graph_join_type] 2089 if opts[:uniq] 2090 opts[:after_load] ||= [] 2091 opts[:after_load].unshift(:array_uniq!) 2092 end 2093 if join_table_db = opts[:join_table_db] 2094 opts[:use_placeholder_loader] = false 2095 opts[:allow_eager_graph] = false 2096 opts[:allow_filtering_by] = false 2097 opts[:eager_limit_strategy] = nil 2098 join_table_ds = join_table_db.from(join_table) 2099 opts[:dataset] ||= proc do |r| 2100 vals = join_table_ds.where(lcks.zip(lcpks.map{|k| get_column_value(k)})).select_map(right) 2101 ds = r.associated_dataset.where(opts.right_primary_key => vals) 2102 if uses_rcks 2103 vals.delete_if{|v| v.any?(&:nil?)} 2104 else 2105 vals.delete(nil) 2106 end 2107 ds = ds.clone(:no_results=>true) if vals.empty? 2108 ds 2109 end 2110 opts[:eager_loader] ||= proc do |eo| 2111 h = eo[:id_map] 2112 assign_singular = opts.assign_singular? 2113 rpk = opts.right_primary_key 2114 name = opts[:name] 2115 2116 join_map = join_table_ds.where(left=>h.keys).select_hash_groups(right, left) 2117 2118 if uses_rcks 2119 join_map.delete_if{|v,| v.any?(&:nil?)} 2120 else 2121 join_map.delete(nil) 2122 end 2123 2124 eo = Hash[eo] 2125 2126 if join_map.empty? 2127 eo[:no_results] = true 2128 else 2129 join_map.each_value do |vs| 2130 vs.replace(vs.flat_map{|v| h[v]}) 2131 vs.uniq! 2132 end 2133 2134 eo[:loader] = false 2135 eo[:right_keys] = join_map.keys 2136 end 2137 2138 opts[:model].eager_load_results(opts, eo) do |assoc_record| 2139 rpkv = if uses_rcks 2140 assoc_record.values.values_at(*rpk) 2141 else 2142 assoc_record.values[rpk] 2143 end 2144 2145 objects = join_map[rpkv] 2146 2147 if assign_singular 2148 objects.each do |object| 2149 object.associations[name] ||= assoc_record 2150 end 2151 else 2152 objects.each do |object| 2153 object.associations[name].push(assoc_record) 2154 end 2155 end 2156 end 2157 end 2158 else 2159 opts[:dataset] ||= opts.association_dataset_proc 2160 opts[:eager_loader] ||= opts.method(:default_eager_loader) 2161 end 2162 2163 join_type = opts[:graph_join_type] 2164 select = opts[:graph_select] 2165 use_only_conditions = opts.include?(:graph_only_conditions) 2166 only_conditions = opts[:graph_only_conditions] 2167 conditions = opts[:graph_conditions] 2168 graph_block = opts[:graph_block] 2169 graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a 2170 use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions) 2171 jt_only_conditions = opts[:graph_join_table_only_conditions] 2172 jt_join_type = opts[:graph_join_table_join_type] 2173 jt_graph_block = opts[:graph_join_table_block] 2174 opts[:eager_grapher] ||= proc do |eo| 2175 ds = eo[:self] 2176 egls = eo[:limit_strategy] 2177 if egls && egls != :ruby 2178 associated_key_array = opts.associated_key_array 2179 orig_egds = egds = eager_graph_dataset(opts, eo) 2180 egds = egds. 2181 inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep). 2182 select_all(egds.first_source). 2183 select_append(*associated_key_array) 2184 egds = opts.apply_eager_graph_limit_strategy(egls, egds) 2185 ds.graph(egds, associated_key_array.map(&:alias).zip(lpkcs) + conditions, :qualify=>:deep, :table_alias=>eo[:table_alias], :implicit_qualifier=>eo[:implicit_qualifier], :join_type=>eo[:join_type]||join_type, :from_self_alias=>eo[:from_self_alias], :join_only=>eo[:join_only], :select=>select||orig_egds.columns, &graph_block) 2186 else 2187 ds = ds.graph(join_table, use_jt_only_conditions ? jt_only_conditions : lcks.zip(lpkcs) + graph_jt_conds, :select=>false, :table_alias=>ds.unused_table_alias(join_table, [eo[:table_alias]]), :join_type=>eo[:join_type]||jt_join_type, :join_only=>eo[:join_only], :implicit_qualifier=>eo[:implicit_qualifier], :qualify=>:deep, :from_self_alias=>eo[:from_self_alias], &jt_graph_block) 2188 ds.graph(eager_graph_dataset(opts, eo), use_only_conditions ? only_conditions : opts.right_primary_keys.zip(rcks) + conditions, :select=>select, :table_alias=>eo[:table_alias], :qualify=>:deep, :join_type=>eo[:join_type]||join_type, :join_only=>eo[:join_only], &graph_block) 2189 end 2190 end 2191 2192 return if opts[:read_only] 2193 2194 if one_through_one 2195 unless opts.has_key?(:setter) 2196 opts[:setter] = proc do |o| 2197 h = {} 2198 lh = lcks.zip(lcpks.map{|k| get_column_value(k)}) 2199 jtds = _join_table_dataset(opts).where(lh) 2200 2201 checked_transaction do 2202 current = jtds.first 2203 2204 if o 2205 new_values = [] 2206 rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))} 2207 end 2208 2209 if current 2210 current_values = rcks.map{|k| current[k]} 2211 jtds = jtds.where(rcks.zip(current_values)) 2212 if o 2213 if current_values != new_values 2214 jtds.update(h) 2215 end 2216 else 2217 jtds.delete 2218 end 2219 elsif o 2220 lh.each{|k,v| h[k] = v} 2221 jtds.insert(h) 2222 end 2223 end 2224 end 2225 end 2226 if opts.fetch(:setter, true) 2227 opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)} 2228 end 2229 else 2230 unless opts.has_key?(:adder) 2231 opts[:adder] = proc do |o| 2232 h = {} 2233 lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)} 2234 rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)} 2235 _join_table_dataset(opts).insert(h) 2236 end 2237 end 2238 2239 unless opts.has_key?(:remover) 2240 opts[:remover] = proc do |o| 2241 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)}) + rcks.zip(opts.right_primary_key_methods.map{|k| o.get_column_value(k)})).delete 2242 end 2243 end 2244 2245 unless opts.has_key?(:clearer) 2246 opts[:clearer] = proc do 2247 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete 2248 end 2249 end 2250 end 2251 end
Configures many_to_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2254 def def_many_to_one(opts) 2255 name = opts[:name] 2256 opts[:key] = opts.default_key unless opts.has_key?(:key) 2257 key = opts[:key] 2258 opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key) 2259 cks = opts[:graph_keys] = opts[:keys] = Array(key) 2260 opts[:key_column] ||= key 2261 opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column]) 2262 opts[:qualified_key] = opts.qualify_cur(key) 2263 if opts[:primary_key] 2264 cpks = Array(opts[:primary_key]) 2265 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2266 end 2267 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2268 opts[:cartesian_product_number] ||= 0 2269 2270 if !opts.has_key?(:many_to_one_pk_lookup) && 2271 (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] || 2272 (opts.has_key?(:key) && opts[:key] == nil)) 2273 opts[:many_to_one_pk_lookup] = false 2274 end 2275 auto_assocs = @autoreloading_associations 2276 cks.each do |k| 2277 (auto_assocs[k] ||= []) << name 2278 end 2279 2280 opts[:dataset] ||= opts.association_dataset_proc 2281 opts[:eager_loader] ||= proc do |eo| 2282 h = eo[:id_map] 2283 pk_meths = opts.primary_key_methods 2284 2285 eager_load_results(opts, eo) do |assoc_record| 2286 hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method) 2287 h[hash_key].each{|object| object.associations[name] = assoc_record} 2288 end 2289 end 2290 2291 join_type = opts[:graph_join_type] 2292 select = opts[:graph_select] 2293 use_only_conditions = opts.include?(:graph_only_conditions) 2294 only_conditions = opts[:graph_only_conditions] 2295 conditions = opts[:graph_conditions] 2296 graph_block = opts[:graph_block] 2297 graph_cks = opts[:graph_keys] 2298 opts[:eager_grapher] ||= proc do |eo| 2299 ds = eo[:self] 2300 ds.graph(eager_graph_dataset(opts, eo), use_only_conditions ? only_conditions : opts.primary_keys.zip(graph_cks) + conditions, eo.merge(:select=>select, :join_type=>eo[:join_type]||join_type, :qualify=>:deep), &graph_block) 2301 end 2302 2303 return if opts[:read_only] 2304 2305 unless opts.has_key?(:setter) 2306 opts[:setter] = proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}} 2307 end 2308 if opts.fetch(:setter, true) 2309 opts[:_setter] = proc{|o| set_associated_object(opts, o)} 2310 end 2311 end
Alias of def_many_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2435 def def_one_through_one(opts) 2436 def_many_to_many(opts) 2437 end
Configures one_to_many
and one_to_one
association reflections and adds the related association methods
# File lib/sequel/model/associations.rb 2314 def def_one_to_many(opts) 2315 one_to_one = opts[:type] == :one_to_one 2316 name = opts[:name] 2317 key = (opts[:key] ||= opts.default_key) 2318 km = opts[:key_method] ||= opts[:key] 2319 cks = opts[:keys] = Array(key) 2320 opts[:key_methods] = Array(opts[:key_method]) 2321 primary_key = (opts[:primary_key] ||= self.primary_key) 2322 opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key) 2323 cpks = opts[:primary_keys] = Array(primary_key) 2324 pkc = opts[:primary_key_column] ||= primary_key 2325 pkcs = opts[:primary_key_columns] ||= Array(pkc) 2326 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2327 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2328 opts[:dataset] ||= opts.association_dataset_proc 2329 opts[:eager_loader] ||= proc do |eo| 2330 h = eo[:id_map] 2331 reciprocal = opts.reciprocal 2332 assign_singular = opts.assign_singular? 2333 delete_rn = opts.delete_row_number_column 2334 2335 eager_load_results(opts, eo) do |assoc_record| 2336 assoc_record.values.delete(delete_rn) if delete_rn 2337 hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km) 2338 objects = h[hash_key] 2339 if assign_singular 2340 objects.each do |object| 2341 unless object.associations[name] 2342 object.associations[name] = assoc_record 2343 assoc_record.associations[reciprocal] = object if reciprocal 2344 end 2345 end 2346 else 2347 objects.each do |object| 2348 object.associations[name].push(assoc_record) 2349 assoc_record.associations[reciprocal] = object if reciprocal 2350 end 2351 end 2352 end 2353 end 2354 2355 join_type = opts[:graph_join_type] 2356 select = opts[:graph_select] 2357 use_only_conditions = opts.include?(:graph_only_conditions) 2358 only_conditions = opts[:graph_only_conditions] 2359 conditions = opts[:graph_conditions] 2360 opts[:cartesian_product_number] ||= one_to_one ? 0 : 1 2361 graph_block = opts[:graph_block] 2362 opts[:eager_grapher] ||= proc do |eo| 2363 ds = eo[:self] 2364 ds = ds.graph(opts.apply_eager_graph_limit_strategy(eo[:limit_strategy], eager_graph_dataset(opts, eo)), use_only_conditions ? only_conditions : cks.zip(pkcs) + conditions, eo.merge(:select=>select, :join_type=>eo[:join_type]||join_type, :qualify=>:deep), &graph_block) 2365 # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense 2366 ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal 2367 ds 2368 end 2369 2370 return if opts[:read_only] 2371 2372 save_opts = {:validate=>opts[:validate]} 2373 ck_nil_hash ={} 2374 cks.each{|k| ck_nil_hash[k] = nil} 2375 2376 if one_to_one 2377 unless opts.has_key?(:setter) 2378 opts[:setter] = proc do |o| 2379 up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))) 2380 2381 if (froms = up_ds.opts[:from]) && (from = froms[0]) && (from.is_a?(Sequel::Dataset) || (from.is_a?(Sequel::SQL::AliasedExpression) && from.expression.is_a?(Sequel::Dataset))) 2382 if old = up_ds.first 2383 cks.each{|k| old.set_column_value(:"#{k}=", nil)} 2384 end 2385 save_old = true 2386 end 2387 2388 if o 2389 if !o.new? && !save_old 2390 up_ds = up_ds.exclude(o.pk_hash) 2391 end 2392 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2393 end 2394 2395 checked_transaction do 2396 if save_old 2397 old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old 2398 else 2399 up_ds.skip_limit_check.update(ck_nil_hash) 2400 end 2401 2402 o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o 2403 end 2404 end 2405 end 2406 if opts.fetch(:setter, true) 2407 opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)} 2408 end 2409 else 2410 save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false 2411 2412 unless opts.has_key?(:adder) 2413 opts[:adder] = proc do |o| 2414 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2415 o.save(save_opts) 2416 end 2417 end 2418 2419 unless opts.has_key?(:remover) 2420 opts[:remover] = proc do |o| 2421 cks.each{|k| o.set_column_value(:"#{k}=", nil)} 2422 o.save(save_opts) 2423 end 2424 end 2425 2426 unless opts.has_key?(:clearer) 2427 opts[:clearer] = proc do 2428 _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash) 2429 end 2430 end 2431 end 2432 end
Alias of def_one_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2440 def def_one_to_one(opts) 2441 def_one_to_many(opts) 2442 end
Return dataset to graph into given the association reflection, applying the :callback option if set.
# File lib/sequel/model/associations.rb 2445 def eager_graph_dataset(opts, eager_options) 2446 ds = opts.associated_class.dataset 2447 if cb = eager_options[:callback] 2448 ds = cb.call(ds) 2449 end 2450 ds 2451 end
If not caching associations, reload the database schema by default, ignoring any cached values.
# File lib/sequel/model/associations.rb 2455 def reload_db_schema? 2456 !@cache_associations 2457 end