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
1610 def all_association_reflections
1611   association_reflections.values
1612 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). Set to nil to not define a add_* method for the association.

: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

:allow_eager_graph

If set to false, you cannot load the association eagerly via eager_graph.

:allow_filtering_by

If set to false, you cannot use the association when filtering

: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). Set to nil to not define a remove_all_* method for the association.

: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

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.

:graph_use_association_block

Makes eager_graph consider the association block. Without this, eager_graph ignores the bock and only use the :graph_* options.

:instance_specific

Marks the association as instance specific. Should be used if the association block uses instance specific state, or transient state (accessing current date/time, etc.).

: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.

:no_association_method

Do not add a method for the association. This can save memory if the association method is never used.

:no_dataset_method

Do not add a method for the association dataset. This can save memory if the dataset method is never used.

: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). Set to nil to not define a remove_* method for the association.

: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). Set to nil to not define a setter method for the association.

: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.

:join_table_db

When retrieving records when using lazy loading or eager loading via eager, instead of a join between to the join table and the associated table, use a separate query for the join table using the given Database object.

: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
1849 def associate(type, name, opts = OPTS, &block)
1850   raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]}
1851   raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol)
1852 
1853   # dup early so we don't modify opts
1854   orig_opts = opts.dup
1855 
1856   if opts[:clone]
1857     cloned_assoc = association_reflection(opts[:clone])
1858     remove_class_name = orig_opts[:class] && !orig_opts[:class_name]
1859     orig_opts = cloned_assoc[:orig_opts].merge(orig_opts)
1860     orig_opts.delete(:class_name) if remove_class_name
1861   end
1862 
1863   opts = Hash[default_association_options]
1864   if type_options = default_association_type_options[type]
1865     opts.merge!(type_options)
1866   end
1867   opts.merge!(orig_opts)
1868   opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self)
1869 
1870   opts[:block] = block if block
1871   opts[:instance_specific] = true if orig_opts[:dataset]
1872   if !opts.has_key?(:instance_specific) && (block || orig_opts[:block])
1873     # It's possible the association is instance specific, in that it depends on
1874     # values other than the foreign key value.  This needs to be checked for
1875     # in certain places to disable optimizations.
1876     opts[:instance_specific] = _association_instance_specific_default(name)
1877   end
1878   if (orig_opts[:instance_specific] || orig_opts[:dataset]) && !opts.has_key?(:allow_eager) && !opts[:eager_loader]
1879     # For associations explicitly marked as instance specific, or that use the
1880     # :dataset option, where :allow_eager is not set, and no :eager_loader is
1881     # provided, disallow eager loading.  In these cases, eager loading is
1882     # unlikely to work.  This is not done for implicit setting of :instance_specific,
1883     # because implicit use is done by default for all associations with blocks,
1884     # and the vast majority of associations with blocks use the block for filtering
1885     # in a manner compatible with eager loading.
1886     opts[:allow_eager] = false
1887   end
1888   opts = assoc_class.new.merge!(opts)
1889 
1890   if opts[:clone] && !opts.cloneable?(cloned_assoc)
1891     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]})")
1892   end
1893 
1894   opts[:use_placeholder_loader] = !opts[:instance_specific] && !opts[:eager_graph]
1895   opts[:eager_block] = opts[:block] unless opts.include?(:eager_block)
1896   opts[:graph_join_type] ||= :left_outer
1897   opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph)
1898   conds = opts[:conditions]
1899   opts[:graph_alias_base] ||= name
1900   opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds)
1901   opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a
1902   opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select]
1903   [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type|
1904     opts[cb_type] = Array(opts[cb_type]) if opts[cb_type]
1905   end
1906 
1907   if opts[:extend]
1908     opts[:extend] = Array(opts[:extend])
1909     opts[:reverse_extend] = opts[:extend].reverse
1910   end
1911 
1912   late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name)
1913   
1914   # Remove :class entry if it exists and is nil, to work with cached_fetch
1915   opts.delete(:class) unless opts[:class]
1916 
1917   def_association(opts)
1918       
1919   orig_opts.delete(:clone)
1920   opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name]
1921   orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block])
1922   opts[:orig_opts] = orig_opts
1923   # don't add to association_reflections until we are sure there are no errors
1924   association_reflections[name] = opts
1925 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
1928 def association_reflection(name)
1929   association_reflections[name]
1930 end
associations() click to toggle source

Array of association name symbols

     # File lib/sequel/model/associations.rb
1933 def associations
1934   association_reflections.keys
1935 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
1938 def eager_load_results(opts, eo, &block)
1939   opts.eager_load_results(eo, &block)
1940 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
1957 def finalize_associations
1958   @association_reflections.each_value(&:finalize)
1959 end
freeze() click to toggle source

Freeze association related metadata when freezing model class.

Calls superclass method
     # File lib/sequel/model/associations.rb
1943 def freeze
1944   @association_reflections.freeze.each_value(&:freeze)
1945   @autoreloading_associations.freeze.each_value(&:freeze)
1946   @default_association_options.freeze
1947   @default_association_type_options.freeze
1948   @default_association_type_options.each_value(&:freeze)
1949 
1950   super
1951 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
1962 def many_to_many(name, opts=OPTS, &block)
1963   associate(:many_to_many, name, opts, &block)
1964 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
1967 def many_to_one(name, opts=OPTS, &block)
1968   associate(:many_to_one, name, opts, &block)
1969 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
1972 def one_through_one(name, opts=OPTS, &block)
1973   associate(:one_through_one, name, opts, &block)
1974 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
1977 def one_to_many(name, opts=OPTS, &block)
1978   associate(:one_to_many, name, opts, &block)
1979 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
1982 def one_to_one(name, opts=OPTS, &block)
1983   associate(:one_to_one, name, opts, &block)
1984 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
1993 def _association_instance_specific_default(_)
1994   true
1995 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
1999 def association_module(opts=OPTS)
2000   opts.fetch(:methods_module, overridable_methods_module)
2001 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
2006 def association_module_def(name, opts=OPTS, &block)
2007   mod = association_module(opts)
2008   mod.send(:define_method, name, &block)
2009   mod.send(:alias_method, name, name)
2010 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
2016 def association_module_delegate_def(name, opts, &block)
2017   mod = association_module(opts)
2018   mod.send(:define_method, name, &block)
2019   # :nocov:
2020   mod.send(:ruby2_keywords, name) if mod.respond_to?(:ruby2_keywords, true)
2021   # :nocov:
2022   mod.send(:alias_method, name, name)
2023 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
2026 def association_module_private_def(name, opts=OPTS, &block)
2027   association_module_def(name, opts, &block)
2028   association_module(opts).send(:private, name)
2029 end
def_association(opts) click to toggle source

Delegate to the type-specific association method to setup the association, and define the association instance methods.

     # File lib/sequel/model/associations.rb
2033 def def_association(opts)
2034   send(:"def_#{opts[:type]}", opts)
2035   def_association_instance_methods(opts)
2036 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
2046 def def_association_instance_methods(opts)
2047   # Always set the method names in the association reflection, even if they
2048   # are not used, for backwards compatibility.
2049   opts[:dataset_method] = :"#{opts[:name]}_dataset"
2050   if opts.returns_array?
2051     sname = singularize(opts[:name])
2052     opts[:_add_method] = :"_add_#{sname}"
2053     opts[:add_method] = :"add_#{sname}"
2054     opts[:_remove_method] = :"_remove_#{sname}"
2055     opts[:remove_method] = :"remove_#{sname}"
2056     opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}"
2057     opts[:remove_all_method] = :"remove_all_#{opts[:name]}"
2058   else
2059     opts[:_setter_method] = :"_#{opts[:name]}="
2060     opts[:setter_method] = :"#{opts[:name]}="
2061   end
2062 
2063   association_module_def(opts.dataset_method, opts){_dataset(opts)} unless opts[:no_dataset_method]
2064   if opts[:block]
2065     opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block])
2066   end
2067   opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1
2068   opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset])
2069   def_association_method(opts) unless opts[:no_association_method]
2070 
2071   return if opts[:read_only]
2072 
2073   if opts[:setter] && opts[:_setter]
2074     # This is backwards due to backwards compatibility
2075     association_module_private_def(opts[:_setter_method], opts, &opts[:setter])
2076     association_module_def(opts[:setter_method], opts, &opts[:_setter])
2077   end
2078 
2079   if adder = opts[:adder]
2080     association_module_private_def(opts[:_add_method], opts, &adder)
2081     association_module_delegate_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)}
2082   end
2083 
2084   if remover = opts[:remover]
2085     association_module_private_def(opts[:_remove_method], opts, &remover)
2086     association_module_delegate_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)}
2087   end
2088 
2089   if clearer = opts[:clearer]
2090     association_module_private_def(opts[:_remove_all_method], opts, &clearer)
2091     association_module_delegate_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)}
2092   end
2093 end
def_association_method(opts) click to toggle source

Adds the association method to the association methods module.

     # File lib/sequel/model/associations.rb
2039 def def_association_method(opts)
2040   association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block|
2041     load_associated_objects(opts, dynamic_opts, &block)
2042   end
2043 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
2096 def def_many_to_many(opts)
2097   one_through_one = opts[:type] == :one_through_one
2098   left = (opts[:left_key] ||= opts.default_left_key)
2099   lcks = opts[:left_keys] = Array(left)
2100   right = (opts[:right_key] ||= opts.default_right_key)
2101   rcks = opts[:right_keys] = Array(right)
2102   left_pk = (opts[:left_primary_key] ||= self.primary_key)
2103   opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key)
2104   lcpks = opts[:left_primary_keys] = Array(left_pk)
2105   lpkc = opts[:left_primary_key_column] ||= left_pk
2106   lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc)
2107   raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length
2108   if opts[:right_primary_key]
2109     rcpks = Array(opts[:right_primary_key])
2110     raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length
2111   end
2112   opts[:uses_left_composite_keys] = lcks.length > 1
2113   uses_rcks = opts[:uses_right_composite_keys] = rcks.length > 1
2114   opts[:cartesian_product_number] ||= one_through_one ? 0 : 1
2115   join_table = (opts[:join_table] ||= opts.default_join_table)
2116   opts[:left_key_alias] ||= opts.default_associated_key_alias
2117   opts[:graph_join_table_join_type] ||= opts[:graph_join_type]
2118   if opts[:uniq]
2119     opts[:after_load] ||= []
2120     opts[:after_load].unshift(:array_uniq!)
2121   end
2122   if join_table_db = opts[:join_table_db]
2123     opts[:use_placeholder_loader] = false
2124     opts[:allow_eager_graph] = false
2125     opts[:allow_filtering_by] = false
2126     opts[:eager_limit_strategy] = nil
2127     join_table_ds = join_table_db.from(join_table)
2128     opts[:dataset] ||= proc do |r|
2129       vals = join_table_ds.where(lcks.zip(lcpks.map{|k| get_column_value(k)})).select_map(right)
2130       ds = r.associated_dataset.where(opts.right_primary_key => vals)
2131       if uses_rcks
2132         vals.delete_if{|v| v.any?(&:nil?)}
2133       else
2134         vals.delete(nil)
2135       end
2136       ds = ds.clone(:no_results=>true) if vals.empty?
2137       ds
2138     end
2139     opts[:eager_loader] ||= proc do |eo|
2140       h = eo[:id_map]
2141       assign_singular = opts.assign_singular?
2142       rpk = opts.right_primary_key
2143       name = opts[:name]
2144 
2145       join_map = join_table_ds.where(left=>h.keys).select_hash_groups(right, left)
2146 
2147       if uses_rcks
2148         join_map.delete_if{|v,| v.any?(&:nil?)}
2149       else
2150         join_map.delete(nil)
2151       end
2152 
2153       eo = Hash[eo]
2154 
2155       if join_map.empty?
2156         eo[:no_results] = true
2157       else
2158         join_map.each_value do |vs|
2159           vs.replace(vs.flat_map{|v| h[v]})
2160           vs.uniq!
2161         end
2162 
2163         eo[:loader] = false
2164         eo[:right_keys] = join_map.keys
2165       end
2166 
2167       opts[:model].eager_load_results(opts, eo) do |assoc_record|
2168         rpkv = if uses_rcks
2169           assoc_record.values.values_at(*rpk)
2170         else
2171           assoc_record.values[rpk]
2172         end
2173 
2174         objects = join_map[rpkv]
2175 
2176         if assign_singular
2177           objects.each do |object|
2178             object.associations[name] ||= assoc_record
2179           end
2180         else
2181           objects.each do |object|
2182             object.associations[name].push(assoc_record)
2183           end
2184         end
2185       end
2186     end
2187   else
2188     opts[:dataset] ||= opts.association_dataset_proc
2189     opts[:eager_loader] ||= opts.method(:default_eager_loader)
2190   end
2191   
2192   join_type = opts[:graph_join_type]
2193   select = opts[:graph_select]
2194   use_only_conditions = opts.include?(:graph_only_conditions)
2195   only_conditions = opts[:graph_only_conditions]
2196   conditions = opts[:graph_conditions]
2197   graph_block = opts[:graph_block]
2198   graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a
2199   use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions)
2200   jt_only_conditions = opts[:graph_join_table_only_conditions]
2201   jt_join_type = opts[:graph_join_table_join_type]
2202   jt_graph_block = opts[:graph_join_table_block]
2203   opts[:eager_grapher] ||= proc do |eo|
2204     ds = eo[:self]
2205     egls = eo[:limit_strategy]
2206     if egls && egls != :ruby
2207       associated_key_array = opts.associated_key_array
2208       orig_egds = egds = eager_graph_dataset(opts, eo)
2209       egds = egds.
2210         inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep).
2211         select_all(egds.first_source).
2212         select_append(*associated_key_array)
2213       egds = opts.apply_eager_graph_limit_strategy(egls, egds)
2214       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)
2215     else
2216       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)
2217       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)
2218     end
2219   end
2220       
2221   return if opts[:read_only]
2222       
2223   if one_through_one
2224     unless opts.has_key?(:setter)
2225       opts[:setter] = proc do |o|
2226         h = {}
2227         lh = lcks.zip(lcpks.map{|k| get_column_value(k)})
2228         jtds = _join_table_dataset(opts).where(lh)
2229 
2230         checked_transaction do
2231           current = jtds.first
2232 
2233           if o
2234             new_values = []
2235             rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))}
2236           end
2237 
2238           if current
2239             current_values = rcks.map{|k| current[k]}
2240             jtds = jtds.where(rcks.zip(current_values))
2241             if o
2242               if current_values != new_values
2243                 jtds.update(h)
2244               end
2245             else
2246               jtds.delete
2247             end
2248           elsif o
2249             lh.each{|k,v| h[k] = v}
2250             jtds.insert(h)
2251           end
2252         end
2253       end
2254     end
2255     if opts.fetch(:setter, true)
2256       opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)}
2257     end
2258   else 
2259     unless opts.has_key?(:adder)
2260       opts[:adder] = proc do |o|
2261         h = {}
2262         lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)}
2263         rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)}
2264         _join_table_dataset(opts).insert(h)
2265       end
2266     end
2267 
2268     unless opts.has_key?(:remover)
2269       opts[:remover] = proc do |o|
2270         _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
2271       end
2272     end
2273 
2274     unless opts.has_key?(:clearer)
2275       opts[:clearer] = proc do
2276         _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete
2277       end
2278     end
2279   end
2280 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
2283 def def_many_to_one(opts)
2284   name = opts[:name]
2285   opts[:key] = opts.default_key unless opts.has_key?(:key)
2286   key = opts[:key]
2287   opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key)
2288   cks = opts[:graph_keys] = opts[:keys] = Array(key)
2289   opts[:key_column] ||= key
2290   opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column])
2291   opts[:qualified_key] = opts.qualify_cur(key)
2292   if opts[:primary_key]
2293     cpks = Array(opts[:primary_key])
2294     raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length
2295   end
2296   uses_cks = opts[:uses_composite_keys] = cks.length > 1
2297   opts[:cartesian_product_number] ||= 0
2298 
2299   if !opts.has_key?(:many_to_one_pk_lookup) &&
2300      (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] ||
2301       (opts.has_key?(:key) && opts[:key] == nil))
2302     opts[:many_to_one_pk_lookup] = false
2303   end
2304   auto_assocs = @autoreloading_associations
2305   cks.each do |k|
2306     (auto_assocs[k] ||= []) << name
2307   end
2308 
2309   opts[:dataset] ||= opts.association_dataset_proc
2310   opts[:eager_loader] ||= proc do |eo|
2311     h = eo[:id_map]
2312     pk_meths = opts.primary_key_methods
2313 
2314     eager_load_results(opts, eo) do |assoc_record|
2315       hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method)
2316       h[hash_key].each{|object| object.associations[name] = assoc_record}
2317     end
2318   end
2319       
2320   join_type = opts[:graph_join_type]
2321   select = opts[:graph_select]
2322   use_only_conditions = opts.include?(:graph_only_conditions)
2323   only_conditions = opts[:graph_only_conditions]
2324   conditions = opts[:graph_conditions]
2325   graph_block = opts[:graph_block]
2326   graph_cks = opts[:graph_keys]
2327   opts[:eager_grapher] ||= proc do |eo|
2328     ds = eo[:self]
2329     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)
2330   end
2331       
2332   return if opts[:read_only]
2333       
2334   unless opts.has_key?(:setter)
2335     opts[:setter] = proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}}
2336   end
2337   if opts.fetch(:setter, true)
2338     opts[:_setter] = proc{|o| set_associated_object(opts, o)}
2339   end
2340 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
2464 def def_one_through_one(opts)
2465   def_many_to_many(opts)
2466 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
2343 def def_one_to_many(opts)
2344   one_to_one = opts[:type] == :one_to_one
2345   name = opts[:name]
2346   key = (opts[:key] ||= opts.default_key)
2347   km = opts[:key_method] ||= opts[:key]
2348   cks = opts[:keys] = Array(key)
2349   opts[:key_methods] = Array(opts[:key_method])
2350   primary_key = (opts[:primary_key] ||= self.primary_key)
2351   opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key)
2352   cpks = opts[:primary_keys] = Array(primary_key)
2353   pkc = opts[:primary_key_column] ||= primary_key
2354   pkcs = opts[:primary_key_columns] ||= Array(pkc)
2355   raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length
2356   uses_cks = opts[:uses_composite_keys] = cks.length > 1
2357   opts[:dataset] ||= opts.association_dataset_proc
2358   opts[:eager_loader] ||= proc do |eo|
2359     h = eo[:id_map]
2360     reciprocal = opts.reciprocal
2361     assign_singular = opts.assign_singular?
2362     delete_rn = opts.delete_row_number_column
2363 
2364     eager_load_results(opts, eo) do |assoc_record|
2365       assoc_record.values.delete(delete_rn) if delete_rn
2366       hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km)
2367       objects = h[hash_key]
2368       if assign_singular
2369         objects.each do |object| 
2370           unless object.associations[name]
2371             object.associations[name] = assoc_record
2372             assoc_record.associations[reciprocal] = object if reciprocal
2373           end
2374         end
2375       else
2376         objects.each do |object| 
2377           object.associations[name].push(assoc_record)
2378           assoc_record.associations[reciprocal] = object if reciprocal
2379         end
2380       end
2381     end
2382   end
2383   
2384   join_type = opts[:graph_join_type]
2385   select = opts[:graph_select]
2386   use_only_conditions = opts.include?(:graph_only_conditions)
2387   only_conditions = opts[:graph_only_conditions]
2388   conditions = opts[:graph_conditions]
2389   opts[:cartesian_product_number] ||= one_to_one ? 0 : 1
2390   graph_block = opts[:graph_block]
2391   opts[:eager_grapher] ||= proc do |eo|
2392     ds = eo[:self]
2393     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)
2394     # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense
2395     ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal
2396     ds
2397   end
2398       
2399   return if opts[:read_only]
2400 
2401   save_opts = {:validate=>opts[:validate]}
2402   ck_nil_hash ={}
2403   cks.each{|k| ck_nil_hash[k] = nil}
2404 
2405   if one_to_one
2406     unless opts.has_key?(:setter)
2407       opts[:setter] = proc do |o|
2408         up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)})))
2409 
2410         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)))
2411           if old = up_ds.first
2412             cks.each{|k| old.set_column_value(:"#{k}=", nil)}
2413           end
2414           save_old = true
2415         end
2416 
2417         if o
2418           if !o.new? && !save_old
2419             up_ds = up_ds.exclude(o.pk_hash)
2420           end
2421           cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))}
2422         end
2423 
2424         checked_transaction do
2425           if save_old
2426             old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old
2427           else
2428             up_ds.skip_limit_check.update(ck_nil_hash)
2429           end
2430 
2431           o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o
2432         end
2433       end
2434     end
2435     if opts.fetch(:setter, true)
2436       opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)}
2437     end
2438   else 
2439     save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false
2440 
2441     unless opts.has_key?(:adder)
2442       opts[:adder] = proc do |o|
2443         cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))}
2444         o.save(save_opts)
2445       end
2446     end
2447     
2448     unless opts.has_key?(:remover)
2449       opts[:remover] = proc do |o|
2450         cks.each{|k| o.set_column_value(:"#{k}=", nil)}
2451         o.save(save_opts)
2452       end
2453     end
2454 
2455     unless opts.has_key?(:clearer)
2456       opts[:clearer] = proc do
2457         _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash)
2458       end
2459     end
2460   end
2461 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
2469 def def_one_to_one(opts)
2470   def_one_to_many(opts)
2471 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
2474 def eager_graph_dataset(opts, eager_options)
2475   ds = opts.associated_class.dataset
2476   if opts[:graph_use_association_block] && (b = opts[:block])
2477     ds = b.call(ds)
2478   end
2479   if cb = eager_options[:callback]
2480     ds = cb.call(ds)
2481   end
2482   ds
2483 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
2487 def reload_db_schema?
2488   !@cache_associations
2489 end