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 1563 def all_association_reflections 1564 association_reflections.values 1565 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).
- :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
- :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).
- :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
-
Over 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.
- :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).
- :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).
- :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.
- :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 1785 def associate(type, name, opts = OPTS, &block) 1786 raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]} 1787 raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol) 1788 1789 # dup early so we don't modify opts 1790 orig_opts = opts.dup 1791 1792 if opts[:clone] 1793 cloned_assoc = association_reflection(opts[:clone]) 1794 orig_opts = cloned_assoc[:orig_opts].merge(orig_opts) 1795 end 1796 1797 opts = Hash[default_association_options] 1798 if type_options = default_association_type_options[type] 1799 opts.merge!(type_options) 1800 end 1801 opts.merge!(orig_opts) 1802 opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self) 1803 1804 opts[:block] = block if block 1805 opts[:instance_specific] = true if orig_opts[:dataset] 1806 if !opts.has_key?(:instance_specific) && (block || orig_opts[:block]) 1807 # It's possible the association is instance specific, in that it depends on 1808 # values other than the foreign key value. This needs to be checked for 1809 # in certain places to disable optimizations. 1810 opts[:instance_specific] = _association_instance_specific_default(name) 1811 end 1812 opts = assoc_class.new.merge!(opts) 1813 1814 if opts[:clone] && !opts.cloneable?(cloned_assoc) 1815 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]})") 1816 end 1817 1818 opts[:use_placeholder_loader] = !opts[:instance_specific] && !opts[:eager_graph] 1819 opts[:eager_block] = opts[:block] unless opts.include?(:eager_block) 1820 opts[:graph_join_type] ||= :left_outer 1821 opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph) 1822 conds = opts[:conditions] 1823 opts[:graph_alias_base] ||= name 1824 opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds) 1825 opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a 1826 opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select] 1827 [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type| 1828 opts[cb_type] = Array(opts[cb_type]) if opts[cb_type] 1829 end 1830 1831 if opts[:extend] 1832 opts[:extend] = Array(opts[:extend]) 1833 opts[:reverse_extend] = opts[:extend].reverse 1834 end 1835 1836 late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name) 1837 1838 # Remove :class entry if it exists and is nil, to work with cached_fetch 1839 opts.delete(:class) unless opts[:class] 1840 1841 send(:"def_#{type}", opts) 1842 def_association_instance_methods(opts) 1843 1844 orig_opts.delete(:clone) 1845 opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name] 1846 orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block]) 1847 opts[:orig_opts] = orig_opts 1848 # don't add to association_reflections until we are sure there are no errors 1849 association_reflections[name] = opts 1850 end
The association reflection hash for the association of the given name.
# File lib/sequel/model/associations.rb 1853 def association_reflection(name) 1854 association_reflections[name] 1855 end
Array
of association name symbols
# File lib/sequel/model/associations.rb 1858 def associations 1859 association_reflections.keys 1860 end
Eager load the association with the given eager loader options.
# File lib/sequel/model/associations.rb 1863 def eager_load_results(opts, eo, &block) 1864 opts.eager_load_results(eo, &block) 1865 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 1882 def finalize_associations 1883 @association_reflections.each_value(&:finalize) 1884 end
Freeze association related metadata when freezing model class.
# File lib/sequel/model/associations.rb 1868 def freeze 1869 @association_reflections.freeze.each_value(&:freeze) 1870 @autoreloading_associations.freeze.each_value(&:freeze) 1871 @default_association_options.freeze 1872 @default_association_type_options.freeze 1873 @default_association_type_options.each_value(&:freeze) 1874 1875 super 1876 end
Shortcut for adding a many_to_many
association, see associate
# File lib/sequel/model/associations.rb 1887 def many_to_many(name, opts=OPTS, &block) 1888 associate(:many_to_many, name, opts, &block) 1889 end
Shortcut for adding a many_to_one
association, see associate
# File lib/sequel/model/associations.rb 1892 def many_to_one(name, opts=OPTS, &block) 1893 associate(:many_to_one, name, opts, &block) 1894 end
Shortcut for adding a one_through_one
association, see associate
# File lib/sequel/model/associations.rb 1897 def one_through_one(name, opts=OPTS, &block) 1898 associate(:one_through_one, name, opts, &block) 1899 end
Shortcut for adding a one_to_many
association, see associate
# File lib/sequel/model/associations.rb 1902 def one_to_many(name, opts=OPTS, &block) 1903 associate(:one_to_many, name, opts, &block) 1904 end
Shortcut for adding a one_to_one
association, see associate
# File lib/sequel/model/associations.rb 1907 def one_to_one(name, opts=OPTS, &block) 1908 associate(:one_to_one, name, opts, &block) 1909 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 1918 def _association_instance_specific_default(_) 1919 true 1920 end
The module to use for the association's methods. Defaults to the overridable_methods_module.
# File lib/sequel/model/associations.rb 1924 def association_module(opts=OPTS) 1925 opts.fetch(:methods_module, overridable_methods_module) 1926 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 1931 def association_module_def(name, opts=OPTS, &block) 1932 mod = association_module(opts) 1933 mod.send(:define_method, name, &block) 1934 mod.send(:alias_method, name, name) 1935 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 1941 def association_module_delegate_def(name, opts, &block) 1942 mod = association_module(opts) 1943 mod.send(:define_method, name, &block) 1944 # :nocov: 1945 mod.send(:ruby2_keywords, name) if mod.respond_to?(:ruby2_keywords, true) 1946 # :nocov: 1947 mod.send(:alias_method, name, name) 1948 end
Add a private method to the module included in the class.
# File lib/sequel/model/associations.rb 1951 def association_module_private_def(name, opts=OPTS, &block) 1952 association_module_def(name, opts, &block) 1953 association_module(opts).send(:private, name) 1954 end
Define all of the association instance methods for this association.
# File lib/sequel/model/associations.rb 1964 def def_association_instance_methods(opts) 1965 # Always set the method names in the association reflection, even if they 1966 # are not used, for backwards compatibility. 1967 opts[:dataset_method] = :"#{opts[:name]}_dataset" 1968 if opts.returns_array? 1969 sname = singularize(opts[:name]) 1970 opts[:_add_method] = :"_add_#{sname}" 1971 opts[:add_method] = :"add_#{sname}" 1972 opts[:_remove_method] = :"_remove_#{sname}" 1973 opts[:remove_method] = :"remove_#{sname}" 1974 opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}" 1975 opts[:remove_all_method] = :"remove_all_#{opts[:name]}" 1976 else 1977 opts[:_setter_method] = :"_#{opts[:name]}=" 1978 opts[:setter_method] = :"#{opts[:name]}=" 1979 end 1980 1981 association_module_def(opts.dataset_method, opts){_dataset(opts)} 1982 if opts[:block] 1983 opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block]) 1984 end 1985 opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1 1986 opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset]) 1987 def_association_method(opts) 1988 1989 return if opts[:read_only] 1990 1991 if opts[:setter] && opts[:_setter] 1992 # This is backwards due to backwards compatibility 1993 association_module_private_def(opts[:_setter_method], opts, &opts[:setter]) 1994 association_module_def(opts[:setter_method], opts, &opts[:_setter]) 1995 end 1996 1997 if adder = opts[:adder] 1998 association_module_private_def(opts[:_add_method], opts, &adder) 1999 association_module_delegate_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)} 2000 end 2001 2002 if remover = opts[:remover] 2003 association_module_private_def(opts[:_remove_method], opts, &remover) 2004 association_module_delegate_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)} 2005 end 2006 2007 if clearer = opts[:clearer] 2008 association_module_private_def(opts[:_remove_all_method], opts, &clearer) 2009 association_module_delegate_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)} 2010 end 2011 end
Adds the association method to the association methods module.
# File lib/sequel/model/associations.rb 1957 def def_association_method(opts) 1958 association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block| 1959 load_associated_objects(opts, dynamic_opts, &block) 1960 end 1961 end
Configures many_to_many
and one_through_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2014 def def_many_to_many(opts) 2015 one_through_one = opts[:type] == :one_through_one 2016 left = (opts[:left_key] ||= opts.default_left_key) 2017 lcks = opts[:left_keys] = Array(left) 2018 right = (opts[:right_key] ||= opts.default_right_key) 2019 rcks = opts[:right_keys] = Array(right) 2020 left_pk = (opts[:left_primary_key] ||= self.primary_key) 2021 opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key) 2022 lcpks = opts[:left_primary_keys] = Array(left_pk) 2023 lpkc = opts[:left_primary_key_column] ||= left_pk 2024 lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc) 2025 raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length 2026 if opts[:right_primary_key] 2027 rcpks = Array(opts[:right_primary_key]) 2028 raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length 2029 end 2030 opts[:uses_left_composite_keys] = lcks.length > 1 2031 opts[:uses_right_composite_keys] = rcks.length > 1 2032 opts[:cartesian_product_number] ||= one_through_one ? 0 : 1 2033 join_table = (opts[:join_table] ||= opts.default_join_table) 2034 opts[:left_key_alias] ||= opts.default_associated_key_alias 2035 opts[:graph_join_table_join_type] ||= opts[:graph_join_type] 2036 if opts[:uniq] 2037 opts[:after_load] ||= [] 2038 opts[:after_load].unshift(:array_uniq!) 2039 end 2040 opts[:dataset] ||= opts.association_dataset_proc 2041 opts[:eager_loader] ||= opts.method(:default_eager_loader) 2042 2043 join_type = opts[:graph_join_type] 2044 select = opts[:graph_select] 2045 use_only_conditions = opts.include?(:graph_only_conditions) 2046 only_conditions = opts[:graph_only_conditions] 2047 conditions = opts[:graph_conditions] 2048 graph_block = opts[:graph_block] 2049 graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a 2050 use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions) 2051 jt_only_conditions = opts[:graph_join_table_only_conditions] 2052 jt_join_type = opts[:graph_join_table_join_type] 2053 jt_graph_block = opts[:graph_join_table_block] 2054 opts[:eager_grapher] ||= proc do |eo| 2055 ds = eo[:self] 2056 egls = eo[:limit_strategy] 2057 if egls && egls != :ruby 2058 associated_key_array = opts.associated_key_array 2059 orig_egds = egds = eager_graph_dataset(opts, eo) 2060 egds = egds. 2061 inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep). 2062 select_all(egds.first_source). 2063 select_append(*associated_key_array) 2064 egds = opts.apply_eager_graph_limit_strategy(egls, egds) 2065 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) 2066 else 2067 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) 2068 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) 2069 end 2070 end 2071 2072 return if opts[:read_only] 2073 2074 if one_through_one 2075 opts[:setter] ||= proc do |o| 2076 h = {} 2077 lh = lcks.zip(lcpks.map{|k| get_column_value(k)}) 2078 jtds = _join_table_dataset(opts).where(lh) 2079 2080 checked_transaction do 2081 current = jtds.first 2082 2083 if o 2084 new_values = [] 2085 rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))} 2086 end 2087 2088 if current 2089 current_values = rcks.map{|k| current[k]} 2090 jtds = jtds.where(rcks.zip(current_values)) 2091 if o 2092 if current_values != new_values 2093 jtds.update(h) 2094 end 2095 else 2096 jtds.delete 2097 end 2098 elsif o 2099 lh.each{|k,v| h[k] = v} 2100 jtds.insert(h) 2101 end 2102 end 2103 end 2104 opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)} 2105 else 2106 opts[:adder] ||= proc do |o| 2107 h = {} 2108 lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)} 2109 rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)} 2110 _join_table_dataset(opts).insert(h) 2111 end 2112 2113 opts[:remover] ||= proc do |o| 2114 _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 2115 end 2116 2117 opts[:clearer] ||= proc do 2118 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete 2119 end 2120 end 2121 end
Configures many_to_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2124 def def_many_to_one(opts) 2125 name = opts[:name] 2126 opts[:key] = opts.default_key unless opts.has_key?(:key) 2127 key = opts[:key] 2128 opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key) 2129 cks = opts[:graph_keys] = opts[:keys] = Array(key) 2130 opts[:key_column] ||= key 2131 opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column]) 2132 opts[:qualified_key] = opts.qualify_cur(key) 2133 if opts[:primary_key] 2134 cpks = Array(opts[:primary_key]) 2135 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2136 end 2137 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2138 opts[:cartesian_product_number] ||= 0 2139 2140 if !opts.has_key?(:many_to_one_pk_lookup) && 2141 (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] || 2142 (opts.has_key?(:key) && opts[:key] == nil)) 2143 opts[:many_to_one_pk_lookup] = false 2144 end 2145 auto_assocs = @autoreloading_associations 2146 cks.each do |k| 2147 (auto_assocs[k] ||= []) << name 2148 end 2149 2150 opts[:dataset] ||= opts.association_dataset_proc 2151 opts[:eager_loader] ||= proc do |eo| 2152 h = eo[:id_map] 2153 pk_meths = opts.primary_key_methods 2154 2155 eager_load_results(opts, eo) do |assoc_record| 2156 hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method) 2157 h[hash_key].each{|object| object.associations[name] = assoc_record} 2158 end 2159 end 2160 2161 join_type = opts[:graph_join_type] 2162 select = opts[:graph_select] 2163 use_only_conditions = opts.include?(:graph_only_conditions) 2164 only_conditions = opts[:graph_only_conditions] 2165 conditions = opts[:graph_conditions] 2166 graph_block = opts[:graph_block] 2167 graph_cks = opts[:graph_keys] 2168 opts[:eager_grapher] ||= proc do |eo| 2169 ds = eo[:self] 2170 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) 2171 end 2172 2173 return if opts[:read_only] 2174 2175 opts[:setter] ||= proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}} 2176 opts[:_setter] = proc{|o| set_associated_object(opts, o)} 2177 end
Alias of def_many_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2291 def def_one_through_one(opts) 2292 def_many_to_many(opts) 2293 end
Configures one_to_many
and one_to_one
association reflections and adds the related association methods
# File lib/sequel/model/associations.rb 2180 def def_one_to_many(opts) 2181 one_to_one = opts[:type] == :one_to_one 2182 name = opts[:name] 2183 key = (opts[:key] ||= opts.default_key) 2184 km = opts[:key_method] ||= opts[:key] 2185 cks = opts[:keys] = Array(key) 2186 opts[:key_methods] = Array(opts[:key_method]) 2187 primary_key = (opts[:primary_key] ||= self.primary_key) 2188 opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key) 2189 cpks = opts[:primary_keys] = Array(primary_key) 2190 pkc = opts[:primary_key_column] ||= primary_key 2191 pkcs = opts[:primary_key_columns] ||= Array(pkc) 2192 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2193 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2194 opts[:dataset] ||= opts.association_dataset_proc 2195 opts[:eager_loader] ||= proc do |eo| 2196 h = eo[:id_map] 2197 reciprocal = opts.reciprocal 2198 assign_singular = opts.assign_singular? 2199 delete_rn = opts.delete_row_number_column 2200 2201 eager_load_results(opts, eo) do |assoc_record| 2202 assoc_record.values.delete(delete_rn) if delete_rn 2203 hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km) 2204 objects = h[hash_key] 2205 if assign_singular 2206 objects.each do |object| 2207 unless object.associations[name] 2208 object.associations[name] = assoc_record 2209 assoc_record.associations[reciprocal] = object if reciprocal 2210 end 2211 end 2212 else 2213 objects.each do |object| 2214 object.associations[name].push(assoc_record) 2215 assoc_record.associations[reciprocal] = object if reciprocal 2216 end 2217 end 2218 end 2219 end 2220 2221 join_type = opts[:graph_join_type] 2222 select = opts[:graph_select] 2223 use_only_conditions = opts.include?(:graph_only_conditions) 2224 only_conditions = opts[:graph_only_conditions] 2225 conditions = opts[:graph_conditions] 2226 opts[:cartesian_product_number] ||= one_to_one ? 0 : 1 2227 graph_block = opts[:graph_block] 2228 opts[:eager_grapher] ||= proc do |eo| 2229 ds = eo[:self] 2230 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) 2231 # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense 2232 ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal 2233 ds 2234 end 2235 2236 return if opts[:read_only] 2237 2238 save_opts = {:validate=>opts[:validate]} 2239 ck_nil_hash ={} 2240 cks.each{|k| ck_nil_hash[k] = nil} 2241 2242 if one_to_one 2243 opts[:setter] ||= proc do |o| 2244 up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))) 2245 2246 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))) 2247 if old = up_ds.first 2248 cks.each{|k| old.set_column_value(:"#{k}=", nil)} 2249 end 2250 save_old = true 2251 end 2252 2253 if o 2254 if !o.new? && !save_old 2255 up_ds = up_ds.exclude(o.pk_hash) 2256 end 2257 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2258 end 2259 2260 checked_transaction do 2261 if save_old 2262 old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old 2263 else 2264 up_ds.skip_limit_check.update(ck_nil_hash) 2265 end 2266 2267 o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o 2268 end 2269 end 2270 opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)} 2271 else 2272 save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false 2273 2274 opts[:adder] ||= proc do |o| 2275 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2276 o.save(save_opts) 2277 end 2278 2279 opts[:remover] ||= proc do |o| 2280 cks.each{|k| o.set_column_value(:"#{k}=", nil)} 2281 o.save(save_opts) 2282 end 2283 2284 opts[:clearer] ||= proc do 2285 _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash) 2286 end 2287 end 2288 end
Alias of def_one_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2296 def def_one_to_one(opts) 2297 def_one_to_many(opts) 2298 end
Return dataset to graph into given the association reflection, applying the :callback option if set.
# File lib/sequel/model/associations.rb 2301 def eager_graph_dataset(opts, eager_options) 2302 ds = opts.associated_class.dataset 2303 if cb = eager_options[:callback] 2304 ds = cb.call(ds) 2305 end 2306 ds 2307 end
If not caching associations, reload the database schema by default, ignoring any cached values.
# File lib/sequel/model/associations.rb 2311 def reload_db_schema? 2312 !@cache_associations 2313 end