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

association_reflections[R]

All association reflections defined for this model (default: {}).

autoreloading_associations[R]

Hash with column symbol keys and arrays of many_to_one association symbols that should be cleared when the column value changes.

cache_associations[RW]

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.

default_association_options[RW]

The default options to use for all associations. This hash is merged into the association reflection hash for all association reflections.

default_association_type_options[RW]

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.

default_eager_limit_strategy[RW]

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

all_association_reflections() click to toggle source

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
associate(type, name, opts = OPTS, &block) click to toggle source

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 to many_to_one, except that the one_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, and one_through_one associations, 1 for one_to_many and many_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 via eager.

: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 via eager_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 via eager_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 or one_to_one associations), or add_/remove_/remove_all_ methods (for one_to_many and many_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 via eager_graph.

:graph_join_table_conditions

The additional conditions to use on the SQL join for the join table when eagerly loading the association via eager_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 via eager_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 via eager_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
association_reflection(name) click to toggle source

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
associations() click to toggle source

Array of association name symbols

     # File lib/sequel/model/associations.rb
1858 def associations
1859   association_reflections.keys
1860 end
eager_load_results(opts, eo, &block) click to toggle source

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_associations() click to toggle source

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() click to toggle source

Freeze association related metadata when freezing model class.

Calls superclass method
     # 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
many_to_many(name, opts=OPTS, &block) click to toggle source

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
many_to_one(name, opts=OPTS, &block) click to toggle source

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
one_through_one(name, opts=OPTS, &block) click to toggle source

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
one_to_many(name, opts=OPTS, &block) click to toggle source

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
one_to_one(name, opts=OPTS, &block) click to toggle source

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

_association_instance_specific_default(_) click to toggle source

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
association_module(opts=OPTS) click to toggle source

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
association_module_def(name, opts=OPTS, &block) click to toggle source

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
association_module_delegate_def(name, opts, &block) click to toggle source

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
association_module_private_def(name, opts=OPTS, &block) click to toggle source

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
def_association_instance_methods(opts) click to toggle source

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
def_association_method(opts) click to toggle source

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
def_many_to_many(opts) click to toggle source

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
def_many_to_one(opts) click to toggle source

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
def_one_through_one(opts) click to toggle source

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
def_one_to_many(opts) click to toggle source

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
def_one_to_one(opts) click to toggle source

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
eager_graph_dataset(opts, eager_options) click to toggle source

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
reload_db_schema?() click to toggle source

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