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
1547 def all_association_reflections
1548   association_reflections.values
1549 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 instance_execed 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.

: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
1768 def associate(type, name, opts = OPTS, &block)
1769   raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]}
1770   raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol)
1771 
1772   # dup early so we don't modify opts
1773   orig_opts = opts.dup
1774 
1775   if opts[:clone]
1776     cloned_assoc = association_reflection(opts[:clone])
1777     orig_opts = cloned_assoc[:orig_opts].merge(orig_opts)
1778   end
1779 
1780   opts = Hash[default_association_options]
1781   if type_options = default_association_type_options[type]
1782     opts.merge!(type_options)
1783   end
1784   opts.merge!(orig_opts)
1785   opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self)
1786 
1787   opts[:block] = block if block
1788   if !opts.has_key?(:instance_specific) && (block || orig_opts[:block] || orig_opts[:dataset])
1789     # It's possible the association is instance specific, in that it depends on
1790     # values other than the foreign key value.  This needs to be checked for
1791     # in certain places to disable optimizations.
1792     opts[:instance_specific] = true
1793   end
1794   opts = assoc_class.new.merge!(opts)
1795 
1796   if opts[:clone] && !opts.cloneable?(cloned_assoc)
1797     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]})")
1798   end
1799 
1800   opts[:eager_block] = opts[:block] unless opts.include?(:eager_block)
1801   opts[:graph_join_type] ||= :left_outer
1802   opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph)
1803   conds = opts[:conditions]
1804   opts[:graph_alias_base] ||= name
1805   opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds)
1806   opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a
1807   opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select]
1808   [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type|
1809     opts[cb_type] = Array(opts[cb_type]) if opts[cb_type]
1810   end
1811 
1812   if opts[:extend]
1813     opts[:extend] = Array(opts[:extend])
1814     opts[:reverse_extend] = opts[:extend].reverse
1815   end
1816 
1817   late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name)
1818   
1819   # Remove :class entry if it exists and is nil, to work with cached_fetch
1820   opts.delete(:class) unless opts[:class]
1821 
1822   send(:"def_#{type}", opts)
1823   def_association_instance_methods(opts)
1824       
1825   orig_opts.delete(:clone)
1826   opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name]
1827   orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block])
1828   opts[:orig_opts] = orig_opts
1829   # don't add to association_reflections until we are sure there are no errors
1830   association_reflections[name] = opts
1831 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
1834 def association_reflection(name)
1835   association_reflections[name]
1836 end
associations() click to toggle source

Array of association name symbols

     # File lib/sequel/model/associations.rb
1839 def associations
1840   association_reflections.keys
1841 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
1844 def eager_load_results(opts, eo, &block)
1845   opts.eager_load_results(eo, &block)
1846 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
1863 def finalize_associations
1864   @association_reflections.each_value(&:finalize)
1865 end
freeze() click to toggle source

Freeze association related metadata when freezing model class.

Calls superclass method
     # File lib/sequel/model/associations.rb
1849 def freeze
1850   @association_reflections.freeze.each_value(&:freeze)
1851   @autoreloading_associations.freeze.each_value(&:freeze)
1852   @default_association_options.freeze
1853   @default_association_type_options.freeze
1854   @default_association_type_options.each_value(&:freeze)
1855 
1856   super
1857 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
1868 def many_to_many(name, opts=OPTS, &block)
1869   associate(:many_to_many, name, opts, &block)
1870 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
1873 def many_to_one(name, opts=OPTS, &block)
1874   associate(:many_to_one, name, opts, &block)
1875 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
1878 def one_through_one(name, opts=OPTS, &block)
1879   associate(:one_through_one, name, opts, &block)
1880 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
1883 def one_to_many(name, opts=OPTS, &block)
1884   associate(:one_to_many, name, opts, &block)
1885 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
1888 def one_to_one(name, opts=OPTS, &block)
1889   associate(:one_to_one, name, opts, &block)
1890 end

Private Instance Methods

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
1899 def association_module(opts=OPTS)
1900   opts.fetch(:methods_module, overridable_methods_module)
1901 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
1906 def association_module_def(name, opts=OPTS, &block)
1907   association_module(opts).module_eval{define_method(name, &block)}
1908 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
1911 def association_module_private_def(name, opts=OPTS, &block)
1912   association_module_def(name, opts, &block)
1913   association_module(opts).send(:private, name)
1914 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
1924 def def_association_instance_methods(opts)
1925   # Always set the method names in the association reflection, even if they
1926   # are not used, for backwards compatibility.
1927   opts[:dataset_method] = :"#{opts[:name]}_dataset"
1928   if opts.returns_array?
1929     sname = singularize(opts[:name])
1930     opts[:_add_method] = :"_add_#{sname}"
1931     opts[:add_method] = :"add_#{sname}"
1932     opts[:_remove_method] = :"_remove_#{sname}"
1933     opts[:remove_method] = :"remove_#{sname}"
1934     opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}"
1935     opts[:remove_all_method] = :"remove_all_#{opts[:name]}"
1936   else
1937     opts[:_setter_method] = :"_#{opts[:name]}="
1938     opts[:setter_method] = :"#{opts[:name]}="
1939   end
1940 
1941   association_module_def(opts.dataset_method, opts){_dataset(opts)}
1942   def_association_method(opts)
1943 
1944   return if opts[:read_only]
1945 
1946   if opts[:setter] && opts[:_setter]
1947     # This is backwards due to backwards compatibility
1948     association_module_private_def(opts[:_setter_method], opts, &opts[:setter])
1949     association_module_def(opts[:setter_method], opts, &opts[:_setter])
1950   end
1951 
1952   if adder = opts[:adder]
1953     association_module_private_def(opts[:_add_method], opts, &adder)
1954     association_module_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)}
1955   end
1956 
1957   if remover = opts[:remover]
1958     association_module_private_def(opts[:_remove_method], opts, &remover)
1959     association_module_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)}
1960   end
1961 
1962   if clearer = opts[:clearer]
1963     association_module_private_def(opts[:_remove_all_method], opts, &clearer)
1964     association_module_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)}
1965   end
1966 end
def_association_method(opts) click to toggle source

Adds the association method to the association methods module.

     # File lib/sequel/model/associations.rb
1917 def def_association_method(opts)
1918   association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block|
1919     load_associated_objects(opts, dynamic_opts, &block)
1920   end
1921 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
1969 def def_many_to_many(opts)
1970   one_through_one = opts[:type] == :one_through_one
1971   left = (opts[:left_key] ||= opts.default_left_key)
1972   lcks = opts[:left_keys] = Array(left)
1973   right = (opts[:right_key] ||= opts.default_right_key)
1974   rcks = opts[:right_keys] = Array(right)
1975   left_pk = (opts[:left_primary_key] ||= self.primary_key)
1976   opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key)
1977   lcpks = opts[:left_primary_keys] = Array(left_pk)
1978   lpkc = opts[:left_primary_key_column] ||= left_pk
1979   lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc)
1980   raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length
1981   if opts[:right_primary_key]
1982     rcpks = Array(opts[:right_primary_key])
1983     raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length
1984   end
1985   opts[:uses_left_composite_keys] = lcks.length > 1
1986   opts[:uses_right_composite_keys] = rcks.length > 1
1987   opts[:cartesian_product_number] ||= one_through_one ? 0 : 1
1988   join_table = (opts[:join_table] ||= opts.default_join_table)
1989   opts[:left_key_alias] ||= opts.default_associated_key_alias
1990   opts[:graph_join_table_join_type] ||= opts[:graph_join_type]
1991   if opts[:uniq]
1992     opts[:after_load] ||= []
1993     opts[:after_load].unshift(:array_uniq!)
1994   end
1995   opts[:dataset] ||= opts.association_dataset_proc
1996   opts[:eager_loader] ||= opts.method(:default_eager_loader)
1997   
1998   join_type = opts[:graph_join_type]
1999   select = opts[:graph_select]
2000   use_only_conditions = opts.include?(:graph_only_conditions)
2001   only_conditions = opts[:graph_only_conditions]
2002   conditions = opts[:graph_conditions]
2003   graph_block = opts[:graph_block]
2004   graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a
2005   use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions)
2006   jt_only_conditions = opts[:graph_join_table_only_conditions]
2007   jt_join_type = opts[:graph_join_table_join_type]
2008   jt_graph_block = opts[:graph_join_table_block]
2009   opts[:eager_grapher] ||= proc do |eo|
2010     ds = eo[:self]
2011     egls = eo[:limit_strategy]
2012     if egls && egls != :ruby
2013       associated_key_array = opts.associated_key_array
2014       orig_egds = egds = eager_graph_dataset(opts, eo)
2015       egds = egds.
2016         inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep).
2017         select_all(egds.first_source).
2018         select_append(*associated_key_array)
2019       egds = opts.apply_eager_graph_limit_strategy(egls, egds)
2020       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)
2021     else
2022       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)
2023       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)
2024     end
2025   end
2026       
2027   return if opts[:read_only]
2028       
2029   if one_through_one
2030     opts[:setter] ||= proc do |o|
2031       h = {}
2032       lh = lcks.zip(lcpks.map{|k| get_column_value(k)})
2033       jtds = _join_table_dataset(opts).where(lh)
2034 
2035       checked_transaction do
2036         current = jtds.first
2037 
2038         if o
2039           new_values = []
2040           rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))}
2041         end
2042 
2043         if current
2044           current_values = rcks.map{|k| current[k]}
2045           jtds = jtds.where(rcks.zip(current_values))
2046           if o
2047             if current_values != new_values
2048               jtds.update(h)
2049             end
2050           else
2051             jtds.delete
2052           end
2053         elsif o
2054           lh.each{|k,v| h[k] = v}
2055           jtds.insert(h)
2056         end
2057       end
2058     end
2059     opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)}
2060   else 
2061     opts[:adder] ||= proc do |o|
2062       h = {}
2063       lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)}
2064       rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)}
2065       _join_table_dataset(opts).insert(h)
2066     end
2067 
2068     opts[:remover] ||= proc do |o|
2069       _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
2070     end
2071 
2072     opts[:clearer] ||= proc do
2073       _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete
2074     end
2075   end
2076 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
2079 def def_many_to_one(opts)
2080   name = opts[:name]
2081   opts[:key] = opts.default_key unless opts.has_key?(:key)
2082   key = opts[:key]
2083   opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key)
2084   cks = opts[:graph_keys] = opts[:keys] = Array(key)
2085   opts[:key_column] ||= key
2086   opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column])
2087   opts[:qualified_key] = opts.qualify_cur(key)
2088   if opts[:primary_key]
2089     cpks = Array(opts[:primary_key])
2090     raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length
2091   end
2092   uses_cks = opts[:uses_composite_keys] = cks.length > 1
2093   opts[:cartesian_product_number] ||= 0
2094 
2095   if !opts.has_key?(:many_to_one_pk_lookup) &&
2096      (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] ||
2097       (opts.has_key?(:key) && opts[:key] == nil))
2098     opts[:many_to_one_pk_lookup] = false
2099   end
2100   auto_assocs = @autoreloading_associations
2101   cks.each do |k|
2102     (auto_assocs[k] ||= []) << name
2103   end
2104 
2105   opts[:dataset] ||= opts.association_dataset_proc
2106   opts[:eager_loader] ||= proc do |eo|
2107     h = eo[:id_map]
2108     pk_meths = opts.primary_key_methods
2109 
2110     eager_load_results(opts, eo) do |assoc_record|
2111       hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method)
2112       if objects = h[hash_key]
2113         objects.each{|object| object.associations[name] = assoc_record}
2114       end
2115     end
2116   end
2117       
2118   join_type = opts[:graph_join_type]
2119   select = opts[:graph_select]
2120   use_only_conditions = opts.include?(:graph_only_conditions)
2121   only_conditions = opts[:graph_only_conditions]
2122   conditions = opts[:graph_conditions]
2123   graph_block = opts[:graph_block]
2124   graph_cks = opts[:graph_keys]
2125   opts[:eager_grapher] ||= proc do |eo|
2126     ds = eo[:self]
2127     ds.graph(eager_graph_dataset(opts, eo), use_only_conditions ? only_conditions : opts.primary_keys.zip(graph_cks) + conditions, Hash[eo].merge!(:select=>select, :join_type=>eo[:join_type]||join_type, :qualify=>:deep, :from_self_alias=>eo[:from_self_alias]), &graph_block)
2128   end
2129       
2130   return if opts[:read_only]
2131       
2132   opts[:setter] ||= proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}}
2133   opts[:_setter] = proc{|o| set_associated_object(opts, o)}
2134 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
2232 def def_one_through_one(opts)
2233   def_many_to_many(opts)
2234 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
2137 def def_one_to_many(opts)
2138   one_to_one = opts[:type] == :one_to_one
2139   name = opts[:name]
2140   key = (opts[:key] ||= opts.default_key)
2141   km = opts[:key_method] ||= opts[:key]
2142   cks = opts[:keys] = Array(key)
2143   opts[:key_methods] = Array(opts[:key_method])
2144   primary_key = (opts[:primary_key] ||= self.primary_key)
2145   opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key)
2146   cpks = opts[:primary_keys] = Array(primary_key)
2147   pkc = opts[:primary_key_column] ||= primary_key
2148   pkcs = opts[:primary_key_columns] ||= Array(pkc)
2149   raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length
2150   uses_cks = opts[:uses_composite_keys] = cks.length > 1
2151   opts[:dataset] ||= opts.association_dataset_proc
2152   opts[:eager_loader] ||= proc do |eo|
2153     h = eo[:id_map]
2154     reciprocal = opts.reciprocal
2155     assign_singular = opts.assign_singular?
2156     delete_rn = opts.delete_row_number_column
2157 
2158     eager_load_results(opts, eo) do |assoc_record|
2159       assoc_record.values.delete(delete_rn) if delete_rn
2160       hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km)
2161       next unless objects = h[hash_key]
2162       if assign_singular
2163         objects.each do |object| 
2164           unless object.associations[name]
2165             object.associations[name] = assoc_record
2166             assoc_record.associations[reciprocal] = object if reciprocal
2167           end
2168         end
2169       else
2170         objects.each do |object| 
2171           object.associations[name].push(assoc_record)
2172           assoc_record.associations[reciprocal] = object if reciprocal
2173         end
2174       end
2175     end
2176   end
2177   
2178   join_type = opts[:graph_join_type]
2179   select = opts[:graph_select]
2180   use_only_conditions = opts.include?(:graph_only_conditions)
2181   only_conditions = opts[:graph_only_conditions]
2182   conditions = opts[:graph_conditions]
2183   opts[:cartesian_product_number] ||= one_to_one ? 0 : 1
2184   graph_block = opts[:graph_block]
2185   opts[:eager_grapher] ||= proc do |eo|
2186     ds = eo[:self]
2187     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, Hash[eo].merge!(:select=>select, :join_type=>eo[:join_type]||join_type, :qualify=>:deep, :from_self_alias=>eo[:from_self_alias]), &graph_block)
2188     # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense
2189     ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal
2190     ds
2191   end
2192       
2193   return if opts[:read_only]
2194 
2195   save_opts = {:validate=>opts[:validate]}
2196   ck_nil_hash ={}
2197   cks.each{|k| ck_nil_hash[k] = nil}
2198 
2199   if one_to_one
2200     opts[:setter] ||= proc do |o|
2201       up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)})))
2202       if o
2203         up_ds = up_ds.exclude(o.pk_hash) unless o.new?
2204         cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))}
2205       end
2206       checked_transaction do
2207         up_ds.skip_limit_check.update(ck_nil_hash)
2208         o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o
2209       end
2210     end
2211     opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)}
2212   else 
2213     save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false
2214 
2215     opts[:adder] ||= proc do |o|
2216       cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))}
2217       o.save(save_opts)
2218     end
2219     
2220     opts[:remover] ||= proc do |o|
2221       cks.each{|k| o.set_column_value(:"#{k}=", nil)}
2222       o.save(save_opts)
2223     end
2224 
2225     opts[:clearer] ||= proc do
2226       _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash)
2227     end
2228   end
2229 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
2237 def def_one_to_one(opts)
2238   def_one_to_many(opts)
2239 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
2242 def eager_graph_dataset(opts, eager_options)
2243   ds = opts.associated_class.dataset
2244   if cb = eager_options[:callback]
2245     ds = cb.call(ds)
2246   end
2247   ds
2248 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
2252 def reload_db_schema?
2253   !@cache_associations
2254 end