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 1566 def all_association_reflections 1567 association_reflections.values 1568 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 1788 def associate(type, name, opts = OPTS, &block) 1789 raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]} 1790 raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol) 1791 1792 # dup early so we don't modify opts 1793 orig_opts = opts.dup 1794 1795 if opts[:clone] 1796 cloned_assoc = association_reflection(opts[:clone]) 1797 orig_opts = cloned_assoc[:orig_opts].merge(orig_opts) 1798 end 1799 1800 opts = Hash[default_association_options] 1801 if type_options = default_association_type_options[type] 1802 opts.merge!(type_options) 1803 end 1804 opts.merge!(orig_opts) 1805 opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self) 1806 1807 opts[:block] = block if block 1808 opts[:instance_specific] = true if orig_opts[:dataset] 1809 if !opts.has_key?(:instance_specific) && (block || orig_opts[:block]) 1810 # It's possible the association is instance specific, in that it depends on 1811 # values other than the foreign key value. This needs to be checked for 1812 # in certain places to disable optimizations. 1813 opts[:instance_specific] = _association_instance_specific_default(name) 1814 end 1815 opts = assoc_class.new.merge!(opts) 1816 1817 if opts[:clone] && !opts.cloneable?(cloned_assoc) 1818 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]})") 1819 end 1820 1821 opts[:use_placeholder_loader] = !opts[:instance_specific] && !opts[:eager_graph] 1822 opts[:eager_block] = opts[:block] unless opts.include?(:eager_block) 1823 opts[:graph_join_type] ||= :left_outer 1824 opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph) 1825 conds = opts[:conditions] 1826 opts[:graph_alias_base] ||= name 1827 opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds) 1828 opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a 1829 opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select] 1830 [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type| 1831 opts[cb_type] = Array(opts[cb_type]) if opts[cb_type] 1832 end 1833 1834 if opts[:extend] 1835 opts[:extend] = Array(opts[:extend]) 1836 opts[:reverse_extend] = opts[:extend].reverse 1837 end 1838 1839 late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name) 1840 1841 # Remove :class entry if it exists and is nil, to work with cached_fetch 1842 opts.delete(:class) unless opts[:class] 1843 1844 send(:"def_#{type}", opts) 1845 def_association_instance_methods(opts) 1846 1847 orig_opts.delete(:clone) 1848 opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name] 1849 orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block]) 1850 opts[:orig_opts] = orig_opts 1851 # don't add to association_reflections until we are sure there are no errors 1852 association_reflections[name] = opts 1853 end
The association reflection hash for the association of the given name.
# File lib/sequel/model/associations.rb 1856 def association_reflection(name) 1857 association_reflections[name] 1858 end
Array
of association name symbols
# File lib/sequel/model/associations.rb 1861 def associations 1862 association_reflections.keys 1863 end
Eager load the association with the given eager loader options.
# File lib/sequel/model/associations.rb 1866 def eager_load_results(opts, eo, &block) 1867 opts.eager_load_results(eo, &block) 1868 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 1885 def finalize_associations 1886 @association_reflections.each_value(&:finalize) 1887 end
Freeze association related metadata when freezing model class.
# File lib/sequel/model/associations.rb 1871 def freeze 1872 @association_reflections.freeze.each_value(&:freeze) 1873 @autoreloading_associations.freeze.each_value(&:freeze) 1874 @default_association_options.freeze 1875 @default_association_type_options.freeze 1876 @default_association_type_options.each_value(&:freeze) 1877 1878 super 1879 end
Shortcut for adding a many_to_many
association, see associate
# File lib/sequel/model/associations.rb 1890 def many_to_many(name, opts=OPTS, &block) 1891 associate(:many_to_many, name, opts, &block) 1892 end
Shortcut for adding a many_to_one
association, see associate
# File lib/sequel/model/associations.rb 1895 def many_to_one(name, opts=OPTS, &block) 1896 associate(:many_to_one, name, opts, &block) 1897 end
Shortcut for adding a one_through_one
association, see associate
# File lib/sequel/model/associations.rb 1900 def one_through_one(name, opts=OPTS, &block) 1901 associate(:one_through_one, name, opts, &block) 1902 end
Shortcut for adding a one_to_many
association, see associate
# File lib/sequel/model/associations.rb 1905 def one_to_many(name, opts=OPTS, &block) 1906 associate(:one_to_many, name, opts, &block) 1907 end
Shortcut for adding a one_to_one
association, see associate
# File lib/sequel/model/associations.rb 1910 def one_to_one(name, opts=OPTS, &block) 1911 associate(:one_to_one, name, opts, &block) 1912 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 1921 def _association_instance_specific_default(_) 1922 true 1923 end
The module to use for the association's methods. Defaults to the overridable_methods_module.
# File lib/sequel/model/associations.rb 1927 def association_module(opts=OPTS) 1928 opts.fetch(:methods_module, overridable_methods_module) 1929 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 1934 def association_module_def(name, opts=OPTS, &block) 1935 mod = association_module(opts) 1936 mod.send(:define_method, name, &block) 1937 mod.send(:alias_method, name, name) 1938 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 1944 def association_module_delegate_def(name, opts, &block) 1945 mod = association_module(opts) 1946 mod.send(:define_method, name, &block) 1947 # :nocov: 1948 mod.send(:ruby2_keywords, name) if mod.respond_to?(:ruby2_keywords, true) 1949 # :nocov: 1950 mod.send(:alias_method, name, name) 1951 end
Add a private method to the module included in the class.
# File lib/sequel/model/associations.rb 1954 def association_module_private_def(name, opts=OPTS, &block) 1955 association_module_def(name, opts, &block) 1956 association_module(opts).send(:private, name) 1957 end
Define all of the association instance methods for this association.
# File lib/sequel/model/associations.rb 1967 def def_association_instance_methods(opts) 1968 # Always set the method names in the association reflection, even if they 1969 # are not used, for backwards compatibility. 1970 opts[:dataset_method] = :"#{opts[:name]}_dataset" 1971 if opts.returns_array? 1972 sname = singularize(opts[:name]) 1973 opts[:_add_method] = :"_add_#{sname}" 1974 opts[:add_method] = :"add_#{sname}" 1975 opts[:_remove_method] = :"_remove_#{sname}" 1976 opts[:remove_method] = :"remove_#{sname}" 1977 opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}" 1978 opts[:remove_all_method] = :"remove_all_#{opts[:name]}" 1979 else 1980 opts[:_setter_method] = :"_#{opts[:name]}=" 1981 opts[:setter_method] = :"#{opts[:name]}=" 1982 end 1983 1984 association_module_def(opts.dataset_method, opts){_dataset(opts)} 1985 if opts[:block] 1986 opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block]) 1987 end 1988 opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1 1989 opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset]) 1990 def_association_method(opts) 1991 1992 return if opts[:read_only] 1993 1994 if opts[:setter] && opts[:_setter] 1995 # This is backwards due to backwards compatibility 1996 association_module_private_def(opts[:_setter_method], opts, &opts[:setter]) 1997 association_module_def(opts[:setter_method], opts, &opts[:_setter]) 1998 end 1999 2000 if adder = opts[:adder] 2001 association_module_private_def(opts[:_add_method], opts, &adder) 2002 association_module_delegate_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)} 2003 end 2004 2005 if remover = opts[:remover] 2006 association_module_private_def(opts[:_remove_method], opts, &remover) 2007 association_module_delegate_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)} 2008 end 2009 2010 if clearer = opts[:clearer] 2011 association_module_private_def(opts[:_remove_all_method], opts, &clearer) 2012 association_module_delegate_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)} 2013 end 2014 end
Adds the association method to the association methods module.
# File lib/sequel/model/associations.rb 1960 def def_association_method(opts) 1961 association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block| 1962 load_associated_objects(opts, dynamic_opts, &block) 1963 end 1964 end
Configures many_to_many
and one_through_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2017 def def_many_to_many(opts) 2018 one_through_one = opts[:type] == :one_through_one 2019 left = (opts[:left_key] ||= opts.default_left_key) 2020 lcks = opts[:left_keys] = Array(left) 2021 right = (opts[:right_key] ||= opts.default_right_key) 2022 rcks = opts[:right_keys] = Array(right) 2023 left_pk = (opts[:left_primary_key] ||= self.primary_key) 2024 opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key) 2025 lcpks = opts[:left_primary_keys] = Array(left_pk) 2026 lpkc = opts[:left_primary_key_column] ||= left_pk 2027 lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc) 2028 raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length 2029 if opts[:right_primary_key] 2030 rcpks = Array(opts[:right_primary_key]) 2031 raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length 2032 end 2033 opts[:uses_left_composite_keys] = lcks.length > 1 2034 opts[:uses_right_composite_keys] = rcks.length > 1 2035 opts[:cartesian_product_number] ||= one_through_one ? 0 : 1 2036 join_table = (opts[:join_table] ||= opts.default_join_table) 2037 opts[:left_key_alias] ||= opts.default_associated_key_alias 2038 opts[:graph_join_table_join_type] ||= opts[:graph_join_type] 2039 if opts[:uniq] 2040 opts[:after_load] ||= [] 2041 opts[:after_load].unshift(:array_uniq!) 2042 end 2043 opts[:dataset] ||= opts.association_dataset_proc 2044 opts[:eager_loader] ||= opts.method(:default_eager_loader) 2045 2046 join_type = opts[:graph_join_type] 2047 select = opts[:graph_select] 2048 use_only_conditions = opts.include?(:graph_only_conditions) 2049 only_conditions = opts[:graph_only_conditions] 2050 conditions = opts[:graph_conditions] 2051 graph_block = opts[:graph_block] 2052 graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a 2053 use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions) 2054 jt_only_conditions = opts[:graph_join_table_only_conditions] 2055 jt_join_type = opts[:graph_join_table_join_type] 2056 jt_graph_block = opts[:graph_join_table_block] 2057 opts[:eager_grapher] ||= proc do |eo| 2058 ds = eo[:self] 2059 egls = eo[:limit_strategy] 2060 if egls && egls != :ruby 2061 associated_key_array = opts.associated_key_array 2062 orig_egds = egds = eager_graph_dataset(opts, eo) 2063 egds = egds. 2064 inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep). 2065 select_all(egds.first_source). 2066 select_append(*associated_key_array) 2067 egds = opts.apply_eager_graph_limit_strategy(egls, egds) 2068 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) 2069 else 2070 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) 2071 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) 2072 end 2073 end 2074 2075 return if opts[:read_only] 2076 2077 if one_through_one 2078 opts[:setter] ||= proc do |o| 2079 h = {} 2080 lh = lcks.zip(lcpks.map{|k| get_column_value(k)}) 2081 jtds = _join_table_dataset(opts).where(lh) 2082 2083 checked_transaction do 2084 current = jtds.first 2085 2086 if o 2087 new_values = [] 2088 rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))} 2089 end 2090 2091 if current 2092 current_values = rcks.map{|k| current[k]} 2093 jtds = jtds.where(rcks.zip(current_values)) 2094 if o 2095 if current_values != new_values 2096 jtds.update(h) 2097 end 2098 else 2099 jtds.delete 2100 end 2101 elsif o 2102 lh.each{|k,v| h[k] = v} 2103 jtds.insert(h) 2104 end 2105 end 2106 end 2107 opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)} 2108 else 2109 opts[:adder] ||= proc do |o| 2110 h = {} 2111 lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)} 2112 rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)} 2113 _join_table_dataset(opts).insert(h) 2114 end 2115 2116 opts[:remover] ||= proc do |o| 2117 _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 2118 end 2119 2120 opts[:clearer] ||= proc do 2121 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete 2122 end 2123 end 2124 end
Configures many_to_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2127 def def_many_to_one(opts) 2128 name = opts[:name] 2129 opts[:key] = opts.default_key unless opts.has_key?(:key) 2130 key = opts[:key] 2131 opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key) 2132 cks = opts[:graph_keys] = opts[:keys] = Array(key) 2133 opts[:key_column] ||= key 2134 opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column]) 2135 opts[:qualified_key] = opts.qualify_cur(key) 2136 if opts[:primary_key] 2137 cpks = Array(opts[:primary_key]) 2138 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2139 end 2140 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2141 opts[:cartesian_product_number] ||= 0 2142 2143 if !opts.has_key?(:many_to_one_pk_lookup) && 2144 (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] || 2145 (opts.has_key?(:key) && opts[:key] == nil)) 2146 opts[:many_to_one_pk_lookup] = false 2147 end 2148 auto_assocs = @autoreloading_associations 2149 cks.each do |k| 2150 (auto_assocs[k] ||= []) << name 2151 end 2152 2153 opts[:dataset] ||= opts.association_dataset_proc 2154 opts[:eager_loader] ||= proc do |eo| 2155 h = eo[:id_map] 2156 pk_meths = opts.primary_key_methods 2157 2158 eager_load_results(opts, eo) do |assoc_record| 2159 hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method) 2160 h[hash_key].each{|object| object.associations[name] = assoc_record} 2161 end 2162 end 2163 2164 join_type = opts[:graph_join_type] 2165 select = opts[:graph_select] 2166 use_only_conditions = opts.include?(:graph_only_conditions) 2167 only_conditions = opts[:graph_only_conditions] 2168 conditions = opts[:graph_conditions] 2169 graph_block = opts[:graph_block] 2170 graph_cks = opts[:graph_keys] 2171 opts[:eager_grapher] ||= proc do |eo| 2172 ds = eo[:self] 2173 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) 2174 end 2175 2176 return if opts[:read_only] 2177 2178 opts[:setter] ||= proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}} 2179 opts[:_setter] = proc{|o| set_associated_object(opts, o)} 2180 end
Alias of def_many_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2294 def def_one_through_one(opts) 2295 def_many_to_many(opts) 2296 end
Configures one_to_many
and one_to_one
association reflections and adds the related association methods
# File lib/sequel/model/associations.rb 2183 def def_one_to_many(opts) 2184 one_to_one = opts[:type] == :one_to_one 2185 name = opts[:name] 2186 key = (opts[:key] ||= opts.default_key) 2187 km = opts[:key_method] ||= opts[:key] 2188 cks = opts[:keys] = Array(key) 2189 opts[:key_methods] = Array(opts[:key_method]) 2190 primary_key = (opts[:primary_key] ||= self.primary_key) 2191 opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key) 2192 cpks = opts[:primary_keys] = Array(primary_key) 2193 pkc = opts[:primary_key_column] ||= primary_key 2194 pkcs = opts[:primary_key_columns] ||= Array(pkc) 2195 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2196 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2197 opts[:dataset] ||= opts.association_dataset_proc 2198 opts[:eager_loader] ||= proc do |eo| 2199 h = eo[:id_map] 2200 reciprocal = opts.reciprocal 2201 assign_singular = opts.assign_singular? 2202 delete_rn = opts.delete_row_number_column 2203 2204 eager_load_results(opts, eo) do |assoc_record| 2205 assoc_record.values.delete(delete_rn) if delete_rn 2206 hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km) 2207 objects = h[hash_key] 2208 if assign_singular 2209 objects.each do |object| 2210 unless object.associations[name] 2211 object.associations[name] = assoc_record 2212 assoc_record.associations[reciprocal] = object if reciprocal 2213 end 2214 end 2215 else 2216 objects.each do |object| 2217 object.associations[name].push(assoc_record) 2218 assoc_record.associations[reciprocal] = object if reciprocal 2219 end 2220 end 2221 end 2222 end 2223 2224 join_type = opts[:graph_join_type] 2225 select = opts[:graph_select] 2226 use_only_conditions = opts.include?(:graph_only_conditions) 2227 only_conditions = opts[:graph_only_conditions] 2228 conditions = opts[:graph_conditions] 2229 opts[:cartesian_product_number] ||= one_to_one ? 0 : 1 2230 graph_block = opts[:graph_block] 2231 opts[:eager_grapher] ||= proc do |eo| 2232 ds = eo[:self] 2233 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) 2234 # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense 2235 ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal 2236 ds 2237 end 2238 2239 return if opts[:read_only] 2240 2241 save_opts = {:validate=>opts[:validate]} 2242 ck_nil_hash ={} 2243 cks.each{|k| ck_nil_hash[k] = nil} 2244 2245 if one_to_one 2246 opts[:setter] ||= proc do |o| 2247 up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))) 2248 2249 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))) 2250 if old = up_ds.first 2251 cks.each{|k| old.set_column_value(:"#{k}=", nil)} 2252 end 2253 save_old = true 2254 end 2255 2256 if o 2257 if !o.new? && !save_old 2258 up_ds = up_ds.exclude(o.pk_hash) 2259 end 2260 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2261 end 2262 2263 checked_transaction do 2264 if save_old 2265 old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old 2266 else 2267 up_ds.skip_limit_check.update(ck_nil_hash) 2268 end 2269 2270 o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o 2271 end 2272 end 2273 opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)} 2274 else 2275 save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false 2276 2277 opts[:adder] ||= proc do |o| 2278 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2279 o.save(save_opts) 2280 end 2281 2282 opts[:remover] ||= proc do |o| 2283 cks.each{|k| o.set_column_value(:"#{k}=", nil)} 2284 o.save(save_opts) 2285 end 2286 2287 opts[:clearer] ||= proc do 2288 _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash) 2289 end 2290 end 2291 end
Alias of def_one_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2299 def def_one_to_one(opts) 2300 def_one_to_many(opts) 2301 end
Return dataset to graph into given the association reflection, applying the :callback option if set.
# File lib/sequel/model/associations.rb 2304 def eager_graph_dataset(opts, eager_options) 2305 ds = opts.associated_class.dataset 2306 if cb = eager_options[:callback] 2307 ds = cb.call(ds) 2308 end 2309 ds 2310 end
If not caching associations, reload the database schema by default, ignoring any cached values.
# File lib/sequel/model/associations.rb 2314 def reload_db_schema? 2315 !@cache_associations 2316 end