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 1552 def all_association_reflections 1553 association_reflections.values 1554 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 1774 def associate(type, name, opts = OPTS, &block) 1775 raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]} 1776 raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol) 1777 1778 # dup early so we don't modify opts 1779 orig_opts = opts.dup 1780 1781 if opts[:clone] 1782 cloned_assoc = association_reflection(opts[:clone]) 1783 orig_opts = cloned_assoc[:orig_opts].merge(orig_opts) 1784 end 1785 1786 opts = Hash[default_association_options] 1787 if type_options = default_association_type_options[type] 1788 opts.merge!(type_options) 1789 end 1790 opts.merge!(orig_opts) 1791 opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self) 1792 1793 opts[:block] = block if block 1794 if !opts.has_key?(:instance_specific) && (block || orig_opts[:block] || orig_opts[:dataset]) 1795 # It's possible the association is instance specific, in that it depends on 1796 # values other than the foreign key value. This needs to be checked for 1797 # in certain places to disable optimizations. 1798 opts[:instance_specific] = true 1799 end 1800 opts = assoc_class.new.merge!(opts) 1801 1802 if opts[:clone] && !opts.cloneable?(cloned_assoc) 1803 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]})") 1804 end 1805 1806 opts[:eager_block] = opts[:block] unless opts.include?(:eager_block) 1807 opts[:graph_join_type] ||= :left_outer 1808 opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph) 1809 conds = opts[:conditions] 1810 opts[:graph_alias_base] ||= name 1811 opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds) 1812 opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a 1813 opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select] 1814 [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type| 1815 opts[cb_type] = Array(opts[cb_type]) if opts[cb_type] 1816 end 1817 1818 if opts[:extend] 1819 opts[:extend] = Array(opts[:extend]) 1820 opts[:reverse_extend] = opts[:extend].reverse 1821 end 1822 1823 late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name) 1824 1825 # Remove :class entry if it exists and is nil, to work with cached_fetch 1826 opts.delete(:class) unless opts[:class] 1827 1828 send(:"def_#{type}", opts) 1829 def_association_instance_methods(opts) 1830 1831 orig_opts.delete(:clone) 1832 opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name] 1833 orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block]) 1834 opts[:orig_opts] = orig_opts 1835 # don't add to association_reflections until we are sure there are no errors 1836 association_reflections[name] = opts 1837 end
The association reflection hash for the association of the given name.
# File lib/sequel/model/associations.rb 1840 def association_reflection(name) 1841 association_reflections[name] 1842 end
Array
of association name symbols
# File lib/sequel/model/associations.rb 1845 def associations 1846 association_reflections.keys 1847 end
Eager load the association with the given eager loader options.
# File lib/sequel/model/associations.rb 1850 def eager_load_results(opts, eo, &block) 1851 opts.eager_load_results(eo, &block) 1852 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 1869 def finalize_associations 1870 @association_reflections.each_value(&:finalize) 1871 end
Freeze association related metadata when freezing model class.
# File lib/sequel/model/associations.rb 1855 def freeze 1856 @association_reflections.freeze.each_value(&:freeze) 1857 @autoreloading_associations.freeze.each_value(&:freeze) 1858 @default_association_options.freeze 1859 @default_association_type_options.freeze 1860 @default_association_type_options.each_value(&:freeze) 1861 1862 super 1863 end
Shortcut for adding a many_to_many
association, see associate
# File lib/sequel/model/associations.rb 1874 def many_to_many(name, opts=OPTS, &block) 1875 associate(:many_to_many, name, opts, &block) 1876 end
Shortcut for adding a many_to_one
association, see associate
# File lib/sequel/model/associations.rb 1879 def many_to_one(name, opts=OPTS, &block) 1880 associate(:many_to_one, name, opts, &block) 1881 end
Shortcut for adding a one_through_one
association, see associate
# File lib/sequel/model/associations.rb 1884 def one_through_one(name, opts=OPTS, &block) 1885 associate(:one_through_one, name, opts, &block) 1886 end
Shortcut for adding a one_to_many
association, see associate
# File lib/sequel/model/associations.rb 1889 def one_to_many(name, opts=OPTS, &block) 1890 associate(:one_to_many, name, opts, &block) 1891 end
Shortcut for adding a one_to_one
association, see associate
# File lib/sequel/model/associations.rb 1894 def one_to_one(name, opts=OPTS, &block) 1895 associate(:one_to_one, name, opts, &block) 1896 end
Private Instance Methods
The module to use for the association's methods. Defaults to the overridable_methods_module.
# File lib/sequel/model/associations.rb 1905 def association_module(opts=OPTS) 1906 opts.fetch(:methods_module, overridable_methods_module) 1907 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 1912 def association_module_def(name, opts=OPTS, &block) 1913 association_module(opts).send(:define_method, name, &block) 1914 end
Add a private method to the module included in the class.
# File lib/sequel/model/associations.rb 1917 def association_module_private_def(name, opts=OPTS, &block) 1918 association_module_def(name, opts, &block) 1919 association_module(opts).send(:private, name) 1920 end
Define all of the association instance methods for this association.
# File lib/sequel/model/associations.rb 1930 def def_association_instance_methods(opts) 1931 # Always set the method names in the association reflection, even if they 1932 # are not used, for backwards compatibility. 1933 opts[:dataset_method] = :"#{opts[:name]}_dataset" 1934 if opts.returns_array? 1935 sname = singularize(opts[:name]) 1936 opts[:_add_method] = :"_add_#{sname}" 1937 opts[:add_method] = :"add_#{sname}" 1938 opts[:_remove_method] = :"_remove_#{sname}" 1939 opts[:remove_method] = :"remove_#{sname}" 1940 opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}" 1941 opts[:remove_all_method] = :"remove_all_#{opts[:name]}" 1942 else 1943 opts[:_setter_method] = :"_#{opts[:name]}=" 1944 opts[:setter_method] = :"#{opts[:name]}=" 1945 end 1946 1947 association_module_def(opts.dataset_method, opts){_dataset(opts)} 1948 if opts[:block] 1949 opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block]) 1950 end 1951 if opts[:dataset] 1952 opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1 1953 opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset]) 1954 end 1955 def_association_method(opts) 1956 1957 return if opts[:read_only] 1958 1959 if opts[:setter] && opts[:_setter] 1960 # This is backwards due to backwards compatibility 1961 association_module_private_def(opts[:_setter_method], opts, &opts[:setter]) 1962 association_module_def(opts[:setter_method], opts, &opts[:_setter]) 1963 end 1964 1965 if adder = opts[:adder] 1966 association_module_private_def(opts[:_add_method], opts, &adder) 1967 association_module_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)} 1968 end 1969 1970 if remover = opts[:remover] 1971 association_module_private_def(opts[:_remove_method], opts, &remover) 1972 association_module_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)} 1973 end 1974 1975 if clearer = opts[:clearer] 1976 association_module_private_def(opts[:_remove_all_method], opts, &clearer) 1977 association_module_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)} 1978 end 1979 end
Adds the association method to the association methods module.
# File lib/sequel/model/associations.rb 1923 def def_association_method(opts) 1924 association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block| 1925 load_associated_objects(opts, dynamic_opts, &block) 1926 end 1927 end
Configures many_to_many
and one_through_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 1982 def def_many_to_many(opts) 1983 one_through_one = opts[:type] == :one_through_one 1984 left = (opts[:left_key] ||= opts.default_left_key) 1985 lcks = opts[:left_keys] = Array(left) 1986 right = (opts[:right_key] ||= opts.default_right_key) 1987 rcks = opts[:right_keys] = Array(right) 1988 left_pk = (opts[:left_primary_key] ||= self.primary_key) 1989 opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key) 1990 lcpks = opts[:left_primary_keys] = Array(left_pk) 1991 lpkc = opts[:left_primary_key_column] ||= left_pk 1992 lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc) 1993 raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length 1994 if opts[:right_primary_key] 1995 rcpks = Array(opts[:right_primary_key]) 1996 raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length 1997 end 1998 opts[:uses_left_composite_keys] = lcks.length > 1 1999 opts[:uses_right_composite_keys] = rcks.length > 1 2000 opts[:cartesian_product_number] ||= one_through_one ? 0 : 1 2001 join_table = (opts[:join_table] ||= opts.default_join_table) 2002 opts[:left_key_alias] ||= opts.default_associated_key_alias 2003 opts[:graph_join_table_join_type] ||= opts[:graph_join_type] 2004 if opts[:uniq] 2005 opts[:after_load] ||= [] 2006 opts[:after_load].unshift(:array_uniq!) 2007 end 2008 opts[:dataset] ||= opts.association_dataset_proc 2009 opts[:eager_loader] ||= opts.method(:default_eager_loader) 2010 2011 join_type = opts[:graph_join_type] 2012 select = opts[:graph_select] 2013 use_only_conditions = opts.include?(:graph_only_conditions) 2014 only_conditions = opts[:graph_only_conditions] 2015 conditions = opts[:graph_conditions] 2016 graph_block = opts[:graph_block] 2017 graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a 2018 use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions) 2019 jt_only_conditions = opts[:graph_join_table_only_conditions] 2020 jt_join_type = opts[:graph_join_table_join_type] 2021 jt_graph_block = opts[:graph_join_table_block] 2022 opts[:eager_grapher] ||= proc do |eo| 2023 ds = eo[:self] 2024 egls = eo[:limit_strategy] 2025 if egls && egls != :ruby 2026 associated_key_array = opts.associated_key_array 2027 orig_egds = egds = eager_graph_dataset(opts, eo) 2028 egds = egds. 2029 inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep). 2030 select_all(egds.first_source). 2031 select_append(*associated_key_array) 2032 egds = opts.apply_eager_graph_limit_strategy(egls, egds) 2033 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) 2034 else 2035 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) 2036 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) 2037 end 2038 end 2039 2040 return if opts[:read_only] 2041 2042 if one_through_one 2043 opts[:setter] ||= proc do |o| 2044 h = {} 2045 lh = lcks.zip(lcpks.map{|k| get_column_value(k)}) 2046 jtds = _join_table_dataset(opts).where(lh) 2047 2048 checked_transaction do 2049 current = jtds.first 2050 2051 if o 2052 new_values = [] 2053 rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))} 2054 end 2055 2056 if current 2057 current_values = rcks.map{|k| current[k]} 2058 jtds = jtds.where(rcks.zip(current_values)) 2059 if o 2060 if current_values != new_values 2061 jtds.update(h) 2062 end 2063 else 2064 jtds.delete 2065 end 2066 elsif o 2067 lh.each{|k,v| h[k] = v} 2068 jtds.insert(h) 2069 end 2070 end 2071 end 2072 opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)} 2073 else 2074 opts[:adder] ||= proc do |o| 2075 h = {} 2076 lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)} 2077 rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)} 2078 _join_table_dataset(opts).insert(h) 2079 end 2080 2081 opts[:remover] ||= proc do |o| 2082 _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 2083 end 2084 2085 opts[:clearer] ||= proc do 2086 _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete 2087 end 2088 end 2089 end
Configures many_to_one
association reflection and adds the related association methods
# File lib/sequel/model/associations.rb 2092 def def_many_to_one(opts) 2093 name = opts[:name] 2094 opts[:key] = opts.default_key unless opts.has_key?(:key) 2095 key = opts[:key] 2096 opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key) 2097 cks = opts[:graph_keys] = opts[:keys] = Array(key) 2098 opts[:key_column] ||= key 2099 opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column]) 2100 opts[:qualified_key] = opts.qualify_cur(key) 2101 if opts[:primary_key] 2102 cpks = Array(opts[:primary_key]) 2103 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2104 end 2105 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2106 opts[:cartesian_product_number] ||= 0 2107 2108 if !opts.has_key?(:many_to_one_pk_lookup) && 2109 (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] || 2110 (opts.has_key?(:key) && opts[:key] == nil)) 2111 opts[:many_to_one_pk_lookup] = false 2112 end 2113 auto_assocs = @autoreloading_associations 2114 cks.each do |k| 2115 (auto_assocs[k] ||= []) << name 2116 end 2117 2118 opts[:dataset] ||= opts.association_dataset_proc 2119 opts[:eager_loader] ||= proc do |eo| 2120 h = eo[:id_map] 2121 pk_meths = opts.primary_key_methods 2122 2123 eager_load_results(opts, eo) do |assoc_record| 2124 hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method) 2125 if objects = h[hash_key] 2126 objects.each{|object| object.associations[name] = assoc_record} 2127 end 2128 end 2129 end 2130 2131 join_type = opts[:graph_join_type] 2132 select = opts[:graph_select] 2133 use_only_conditions = opts.include?(:graph_only_conditions) 2134 only_conditions = opts[:graph_only_conditions] 2135 conditions = opts[:graph_conditions] 2136 graph_block = opts[:graph_block] 2137 graph_cks = opts[:graph_keys] 2138 opts[:eager_grapher] ||= proc do |eo| 2139 ds = eo[:self] 2140 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) 2141 end 2142 2143 return if opts[:read_only] 2144 2145 opts[:setter] ||= proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}} 2146 opts[:_setter] = proc{|o| set_associated_object(opts, o)} 2147 end
Alias of def_many_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2261 def def_one_through_one(opts) 2262 def_many_to_many(opts) 2263 end
Configures one_to_many
and one_to_one
association reflections and adds the related association methods
# File lib/sequel/model/associations.rb 2150 def def_one_to_many(opts) 2151 one_to_one = opts[:type] == :one_to_one 2152 name = opts[:name] 2153 key = (opts[:key] ||= opts.default_key) 2154 km = opts[:key_method] ||= opts[:key] 2155 cks = opts[:keys] = Array(key) 2156 opts[:key_methods] = Array(opts[:key_method]) 2157 primary_key = (opts[:primary_key] ||= self.primary_key) 2158 opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key) 2159 cpks = opts[:primary_keys] = Array(primary_key) 2160 pkc = opts[:primary_key_column] ||= primary_key 2161 pkcs = opts[:primary_key_columns] ||= Array(pkc) 2162 raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length 2163 uses_cks = opts[:uses_composite_keys] = cks.length > 1 2164 opts[:dataset] ||= opts.association_dataset_proc 2165 opts[:eager_loader] ||= proc do |eo| 2166 h = eo[:id_map] 2167 reciprocal = opts.reciprocal 2168 assign_singular = opts.assign_singular? 2169 delete_rn = opts.delete_row_number_column 2170 2171 eager_load_results(opts, eo) do |assoc_record| 2172 assoc_record.values.delete(delete_rn) if delete_rn 2173 hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km) 2174 next unless objects = h[hash_key] 2175 if assign_singular 2176 objects.each do |object| 2177 unless object.associations[name] 2178 object.associations[name] = assoc_record 2179 assoc_record.associations[reciprocal] = object if reciprocal 2180 end 2181 end 2182 else 2183 objects.each do |object| 2184 object.associations[name].push(assoc_record) 2185 assoc_record.associations[reciprocal] = object if reciprocal 2186 end 2187 end 2188 end 2189 end 2190 2191 join_type = opts[:graph_join_type] 2192 select = opts[:graph_select] 2193 use_only_conditions = opts.include?(:graph_only_conditions) 2194 only_conditions = opts[:graph_only_conditions] 2195 conditions = opts[:graph_conditions] 2196 opts[:cartesian_product_number] ||= one_to_one ? 0 : 1 2197 graph_block = opts[:graph_block] 2198 opts[:eager_grapher] ||= proc do |eo| 2199 ds = eo[:self] 2200 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) 2201 # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense 2202 ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal 2203 ds 2204 end 2205 2206 return if opts[:read_only] 2207 2208 save_opts = {:validate=>opts[:validate]} 2209 ck_nil_hash ={} 2210 cks.each{|k| ck_nil_hash[k] = nil} 2211 2212 if one_to_one 2213 opts[:setter] ||= proc do |o| 2214 up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))) 2215 2216 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))) 2217 if old = up_ds.first 2218 cks.each{|k| old.set_column_value(:"#{k}=", nil)} 2219 end 2220 save_old = true 2221 end 2222 2223 if o 2224 if !o.new? && !save_old 2225 up_ds = up_ds.exclude(o.pk_hash) 2226 end 2227 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2228 end 2229 2230 checked_transaction do 2231 if save_old 2232 old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old 2233 else 2234 up_ds.skip_limit_check.update(ck_nil_hash) 2235 end 2236 2237 o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o 2238 end 2239 end 2240 opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)} 2241 else 2242 save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false 2243 2244 opts[:adder] ||= proc do |o| 2245 cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))} 2246 o.save(save_opts) 2247 end 2248 2249 opts[:remover] ||= proc do |o| 2250 cks.each{|k| o.set_column_value(:"#{k}=", nil)} 2251 o.save(save_opts) 2252 end 2253 2254 opts[:clearer] ||= proc do 2255 _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash) 2256 end 2257 end 2258 end
Alias of def_one_to_many
, since they share pretty much the same code.
# File lib/sequel/model/associations.rb 2266 def def_one_to_one(opts) 2267 def_one_to_many(opts) 2268 end
Return dataset to graph into given the association reflection, applying the :callback option if set.
# File lib/sequel/model/associations.rb 2271 def eager_graph_dataset(opts, eager_options) 2272 ds = opts.associated_class.dataset 2273 if cb = eager_options[:callback] 2274 ds = cb.call(ds) 2275 end 2276 ds 2277 end
If not caching associations, reload the database schema by default, ignoring any cached values.
# File lib/sequel/model/associations.rb 2281 def reload_db_schema? 2282 !@cache_associations 2283 end