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
1621 def all_association_reflections
1622   association_reflections.values
1623 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.

:eager_loading_predicate_transform

A callable object with which to transform the predicate key values used when eager loading. Called with two arguments, the array of predicate key values, and a the reflection for the association being eager loaded.

: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.

:use_placeholder_loader

Whether to use a placeholder loader when eager loading the association. Can be set to false to disable the use of a placeholder loader if one would be used by default.

: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
1866 def associate(type, name, opts = OPTS, &block)
1867   raise(Error, 'invalid association type') unless assoc_class = Sequel.synchronize{ASSOCIATION_TYPES[type]}
1868   raise(Error, 'Model.associate name argument must be a symbol') unless name.is_a?(Symbol)
1869 
1870   # dup early so we don't modify opts
1871   orig_opts = opts.dup
1872 
1873   if opts[:clone]
1874     cloned_assoc = association_reflection(opts[:clone])
1875     remove_class_name = orig_opts[:class] && !orig_opts[:class_name]
1876     orig_opts = cloned_assoc[:orig_opts].merge(orig_opts)
1877     orig_opts.delete(:class_name) if remove_class_name
1878   end
1879 
1880   opts = Hash[default_association_options]
1881   if type_options = default_association_type_options[type]
1882     opts.merge!(type_options)
1883   end
1884   opts.merge!(orig_opts)
1885   opts.merge!(:type => type, :name => name, :cache=>({} if cache_associations), :model => self)
1886 
1887   opts[:block] = block if block
1888   opts[:instance_specific] = true if orig_opts[:dataset]
1889   if !opts.has_key?(:instance_specific) && (block || orig_opts[:block])
1890     # It's possible the association is instance specific, in that it depends on
1891     # values other than the foreign key value.  This needs to be checked for
1892     # in certain places to disable optimizations.
1893     opts[:instance_specific] = _association_instance_specific_default(name)
1894   end
1895   if (orig_opts[:instance_specific] || orig_opts[:dataset]) && !opts.has_key?(:allow_eager) && !opts[:eager_loader]
1896     # For associations explicitly marked as instance specific, or that use the
1897     # :dataset option, where :allow_eager is not set, and no :eager_loader is
1898     # provided, disallow eager loading.  In these cases, eager loading is
1899     # unlikely to work.  This is not done for implicit setting of :instance_specific,
1900     # because implicit use is done by default for all associations with blocks,
1901     # and the vast majority of associations with blocks use the block for filtering
1902     # in a manner compatible with eager loading.
1903     opts[:allow_eager] = false
1904   end
1905   opts = assoc_class.new.merge!(opts)
1906 
1907   if opts[:clone] && !opts.cloneable?(cloned_assoc)
1908     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]})")
1909   end
1910 
1911   opts[:use_placeholder_loader] = !opts[:instance_specific] && !opts[:eager_graph] unless opts.include?(:use_placeholder_loader)
1912   opts[:eager_block] = opts[:block] unless opts.include?(:eager_block)
1913   opts[:graph_join_type] ||= :left_outer
1914   opts[:order_eager_graph] = true unless opts.include?(:order_eager_graph)
1915   conds = opts[:conditions]
1916   opts[:graph_alias_base] ||= name
1917   opts[:graph_conditions] = conds if !opts.include?(:graph_conditions) and Sequel.condition_specifier?(conds)
1918   opts[:graph_conditions] = opts.fetch(:graph_conditions, []).to_a
1919   opts[:graph_select] = Array(opts[:graph_select]) if opts[:graph_select]
1920   [:before_add, :before_remove, :after_add, :after_remove, :after_load, :before_set, :after_set].each do |cb_type|
1921     opts[cb_type] = Array(opts[cb_type]) if opts[cb_type]
1922   end
1923 
1924   if opts[:extend]
1925     opts[:extend] = Array(opts[:extend])
1926     opts[:reverse_extend] = opts[:extend].reverse
1927   end
1928 
1929   late_binding_class_option(opts, opts.returns_array? ? singularize(name) : name)
1930   
1931   # Remove :class entry if it exists and is nil, to work with cached_fetch
1932   opts.delete(:class) unless opts[:class]
1933 
1934   def_association(opts)
1935       
1936   orig_opts.delete(:clone)
1937   opts[:orig_class] = orig_opts[:class] || orig_opts[:class_name]
1938   orig_opts.merge!(:class_name=>opts[:class_name], :class=>opts[:class], :block=>opts[:block])
1939   opts[:orig_opts] = orig_opts
1940   # don't add to association_reflections until we are sure there are no errors
1941   association_reflections[name] = opts
1942 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
1945 def association_reflection(name)
1946   association_reflections[name]
1947 end
associations() click to toggle source

Array of association name symbols

     # File lib/sequel/model/associations.rb
1950 def associations
1951   association_reflections.keys
1952 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
1955 def eager_load_results(opts, eo, &block)
1956   opts.eager_load_results(eo, &block)
1957 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
1974 def finalize_associations
1975   @association_reflections.each_value(&:finalize)
1976 end
freeze() click to toggle source

Freeze association related metadata when freezing model class.

Calls superclass method
     # File lib/sequel/model/associations.rb
1960 def freeze
1961   @association_reflections.freeze.each_value(&:freeze)
1962   @autoreloading_associations.freeze.each_value(&:freeze)
1963   @default_association_options.freeze
1964   @default_association_type_options.freeze
1965   @default_association_type_options.each_value(&:freeze)
1966 
1967   super
1968 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
1979 def many_to_many(name, opts=OPTS, &block)
1980   associate(:many_to_many, name, opts, &block)
1981 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
1984 def many_to_one(name, opts=OPTS, &block)
1985   associate(:many_to_one, name, opts, &block)
1986 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
1989 def one_through_one(name, opts=OPTS, &block)
1990   associate(:one_through_one, name, opts, &block)
1991 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
1994 def one_to_many(name, opts=OPTS, &block)
1995   associate(:one_to_many, name, opts, &block)
1996 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
1999 def one_to_one(name, opts=OPTS, &block)
2000   associate(:one_to_one, name, opts, &block)
2001 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
2010 def _association_instance_specific_default(_)
2011   true
2012 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
2016 def association_module(opts=OPTS)
2017   opts.fetch(:methods_module, overridable_methods_module)
2018 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
2023 def association_module_def(name, opts=OPTS, &block)
2024   mod = association_module(opts)
2025   mod.send(:define_method, name, &block)
2026   mod.send(:alias_method, name, name)
2027 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
2033 def association_module_delegate_def(name, opts, &block)
2034   mod = association_module(opts)
2035   mod.send(:define_method, name, &block)
2036   # :nocov:
2037   mod.send(:ruby2_keywords, name) if mod.respond_to?(:ruby2_keywords, true)
2038   # :nocov:
2039   mod.send(:alias_method, name, name)
2040 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
2043 def association_module_private_def(name, opts=OPTS, &block)
2044   association_module_def(name, opts, &block)
2045   association_module(opts).send(:private, name)
2046 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
2050 def def_association(opts)
2051   send(:"def_#{opts[:type]}", opts)
2052   def_association_instance_methods(opts)
2053 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
2063 def def_association_instance_methods(opts)
2064   # Always set the method names in the association reflection, even if they
2065   # are not used, for backwards compatibility.
2066   opts[:dataset_method] = :"#{opts[:name]}_dataset"
2067   if opts.returns_array?
2068     sname = singularize(opts[:name])
2069     opts[:_add_method] = :"_add_#{sname}"
2070     opts[:add_method] = :"add_#{sname}"
2071     opts[:_remove_method] = :"_remove_#{sname}"
2072     opts[:remove_method] = :"remove_#{sname}"
2073     opts[:_remove_all_method] = :"_remove_all_#{opts[:name]}"
2074     opts[:remove_all_method] = :"remove_all_#{opts[:name]}"
2075   else
2076     opts[:_setter_method] = :"_#{opts[:name]}="
2077     opts[:setter_method] = :"#{opts[:name]}="
2078   end
2079 
2080   association_module_def(opts.dataset_method, opts){_dataset(opts)} unless opts[:no_dataset_method]
2081   if opts[:block]
2082     opts[:block_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_block", 1, &opts[:block])
2083   end
2084   opts[:dataset_opt_arity] = opts[:dataset].arity == 0 ? 0 : 1
2085   opts[:dataset_opt_method] = Plugins.def_sequel_method(association_module(opts), "#{opts[:name]}_dataset_opt", opts[:dataset_opt_arity], &opts[:dataset])
2086   def_association_method(opts) unless opts[:no_association_method]
2087 
2088   return if opts[:read_only]
2089 
2090   if opts[:setter] && opts[:_setter]
2091     # This is backwards due to backwards compatibility
2092     association_module_private_def(opts[:_setter_method], opts, &opts[:setter])
2093     association_module_def(opts[:setter_method], opts, &opts[:_setter])
2094   end
2095 
2096   if adder = opts[:adder]
2097     association_module_private_def(opts[:_add_method], opts, &adder)
2098     association_module_delegate_def(opts[:add_method], opts){|o,*args| add_associated_object(opts, o, *args)}
2099   end
2100 
2101   if remover = opts[:remover]
2102     association_module_private_def(opts[:_remove_method], opts, &remover)
2103     association_module_delegate_def(opts[:remove_method], opts){|o,*args| remove_associated_object(opts, o, *args)}
2104   end
2105 
2106   if clearer = opts[:clearer]
2107     association_module_private_def(opts[:_remove_all_method], opts, &clearer)
2108     association_module_delegate_def(opts[:remove_all_method], opts){|*args| remove_all_associated_objects(opts, *args)}
2109   end
2110 end
def_association_method(opts) click to toggle source

Adds the association method to the association methods module.

     # File lib/sequel/model/associations.rb
2056 def def_association_method(opts)
2057   association_module_def(opts.association_method, opts) do |dynamic_opts=OPTS, &block|
2058     load_associated_objects(opts, dynamic_opts, &block)
2059   end
2060 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
2113 def def_many_to_many(opts)
2114   one_through_one = opts[:type] == :one_through_one
2115   left = (opts[:left_key] ||= opts.default_left_key)
2116   lcks = opts[:left_keys] = Array(left)
2117   right = (opts[:right_key] ||= opts.default_right_key)
2118   rcks = opts[:right_keys] = Array(right)
2119   left_pk = (opts[:left_primary_key] ||= self.primary_key)
2120   opts[:eager_loader_key] = left_pk unless opts.has_key?(:eager_loader_key)
2121   lcpks = opts[:left_primary_keys] = Array(left_pk)
2122   lpkc = opts[:left_primary_key_column] ||= left_pk
2123   lpkcs = opts[:left_primary_key_columns] ||= Array(lpkc)
2124   raise(Error, "mismatched number of left keys: #{lcks.inspect} vs #{lcpks.inspect}") unless lcks.length == lcpks.length
2125   if opts[:right_primary_key]
2126     rcpks = Array(opts[:right_primary_key])
2127     raise(Error, "mismatched number of right keys: #{rcks.inspect} vs #{rcpks.inspect}") unless rcks.length == rcpks.length
2128   end
2129   opts[:uses_left_composite_keys] = lcks.length > 1
2130   uses_rcks = opts[:uses_right_composite_keys] = rcks.length > 1
2131   opts[:cartesian_product_number] ||= one_through_one ? 0 : 1
2132   join_table = (opts[:join_table] ||= opts.default_join_table)
2133   opts[:left_key_alias] ||= opts.default_associated_key_alias
2134   opts[:graph_join_table_join_type] ||= opts[:graph_join_type]
2135   if opts[:uniq]
2136     opts[:after_load] ||= []
2137     opts[:after_load].unshift(:array_uniq!)
2138   end
2139   if join_table_db = opts[:join_table_db]
2140     opts[:use_placeholder_loader] = false
2141     opts[:allow_eager_graph] = false
2142     opts[:allow_filtering_by] = false
2143     opts[:eager_limit_strategy] = nil
2144     join_table_ds = join_table_db.from(join_table)
2145     opts[:dataset] ||= proc do |r|
2146       vals = join_table_ds.where(lcks.zip(lcpks.map{|k| get_column_value(k)})).select_map(right)
2147       ds = r.associated_dataset.where(opts.right_primary_key => vals)
2148       if uses_rcks
2149         vals.delete_if{|v| v.any?(&:nil?)}
2150       else
2151         vals.delete(nil)
2152       end
2153       ds = ds.clone(:no_results=>true) if vals.empty?
2154       ds
2155     end
2156     opts[:eager_loader] ||= proc do |eo|
2157       h = eo[:id_map]
2158       assign_singular = opts.assign_singular?
2159       rpk = opts.right_primary_key
2160       name = opts[:name]
2161 
2162       join_map = join_table_ds.where(left=>h.keys).select_hash_groups(right, left)
2163 
2164       if uses_rcks
2165         join_map.delete_if{|v,| v.any?(&:nil?)}
2166       else
2167         join_map.delete(nil)
2168       end
2169 
2170       eo = Hash[eo]
2171 
2172       if join_map.empty?
2173         eo[:no_results] = true
2174       else
2175         join_map.each_value do |vs|
2176           vs.replace(vs.flat_map{|v| h[v]})
2177           vs.uniq!
2178         end
2179 
2180         eo[:loader] = false
2181         eo[:right_keys] = join_map.keys
2182       end
2183 
2184       opts[:model].eager_load_results(opts, eo) do |assoc_record|
2185         rpkv = if uses_rcks
2186           assoc_record.values.values_at(*rpk)
2187         else
2188           assoc_record.values[rpk]
2189         end
2190 
2191         objects = join_map[rpkv]
2192 
2193         if assign_singular
2194           objects.each do |object|
2195             object.associations[name] ||= assoc_record
2196           end
2197         else
2198           objects.each do |object|
2199             object.associations[name].push(assoc_record)
2200           end
2201         end
2202       end
2203     end
2204   else
2205     opts[:dataset] ||= opts.association_dataset_proc
2206     opts[:eager_loader] ||= opts.method(:default_eager_loader)
2207   end
2208   
2209   join_type = opts[:graph_join_type]
2210   select = opts[:graph_select]
2211   use_only_conditions = opts.include?(:graph_only_conditions)
2212   only_conditions = opts[:graph_only_conditions]
2213   conditions = opts[:graph_conditions]
2214   graph_block = opts[:graph_block]
2215   graph_jt_conds = opts[:graph_join_table_conditions] = opts.fetch(:graph_join_table_conditions, []).to_a
2216   use_jt_only_conditions = opts.include?(:graph_join_table_only_conditions)
2217   jt_only_conditions = opts[:graph_join_table_only_conditions]
2218   jt_join_type = opts[:graph_join_table_join_type]
2219   jt_graph_block = opts[:graph_join_table_block]
2220   opts[:eager_grapher] ||= proc do |eo|
2221     ds = eo[:self]
2222     egls = eo[:limit_strategy]
2223     if egls && egls != :ruby
2224       associated_key_array = opts.associated_key_array
2225       orig_egds = egds = eager_graph_dataset(opts, eo)
2226       egds = egds.
2227         inner_join(join_table, rcks.zip(opts.right_primary_keys) + graph_jt_conds, :qualify=>:deep).
2228         select_all(egds.first_source).
2229         select_append(*associated_key_array)
2230       egds = opts.apply_eager_graph_limit_strategy(egls, egds)
2231       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)
2232     else
2233       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)
2234       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)
2235     end
2236   end
2237       
2238   return if opts[:read_only]
2239       
2240   if one_through_one
2241     unless opts.has_key?(:setter)
2242       opts[:setter] = proc do |o|
2243         h = {}
2244         lh = lcks.zip(lcpks.map{|k| get_column_value(k)})
2245         jtds = _join_table_dataset(opts).where(lh)
2246 
2247         checked_transaction do
2248           current = jtds.first
2249 
2250           if o
2251             new_values = []
2252             rcks.zip(opts.right_primary_key_methods).each{|k, pk| new_values << (h[k] = o.get_column_value(pk))}
2253           end
2254 
2255           if current
2256             current_values = rcks.map{|k| current[k]}
2257             jtds = jtds.where(rcks.zip(current_values))
2258             if o
2259               if current_values != new_values
2260                 jtds.update(h)
2261               end
2262             else
2263               jtds.delete
2264             end
2265           elsif o
2266             lh.each{|k,v| h[k] = v}
2267             jtds.insert(h)
2268           end
2269         end
2270       end
2271     end
2272     if opts.fetch(:setter, true)
2273       opts[:_setter] = proc{|o| set_one_through_one_associated_object(opts, o)}
2274     end
2275   else 
2276     unless opts.has_key?(:adder)
2277       opts[:adder] = proc do |o|
2278         h = {}
2279         lcks.zip(lcpks).each{|k, pk| h[k] = get_column_value(pk)}
2280         rcks.zip(opts.right_primary_key_methods).each{|k, pk| h[k] = o.get_column_value(pk)}
2281         _join_table_dataset(opts).insert(h)
2282       end
2283     end
2284 
2285     unless opts.has_key?(:remover)
2286       opts[:remover] = proc do |o|
2287         _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
2288       end
2289     end
2290 
2291     unless opts.has_key?(:clearer)
2292       opts[:clearer] = proc do
2293         _join_table_dataset(opts).where(lcks.zip(lcpks.map{|k| get_column_value(k)})).delete
2294       end
2295     end
2296   end
2297 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
2300 def def_many_to_one(opts)
2301   name = opts[:name]
2302   opts[:key] = opts.default_key unless opts.has_key?(:key)
2303   key = opts[:key]
2304   opts[:eager_loader_key] = key unless opts.has_key?(:eager_loader_key)
2305   cks = opts[:graph_keys] = opts[:keys] = Array(key)
2306   opts[:key_column] ||= key
2307   opts[:graph_keys] = opts[:key_columns] = Array(opts[:key_column])
2308   opts[:qualified_key] = opts.qualify_cur(key)
2309   if opts[:primary_key]
2310     cpks = Array(opts[:primary_key])
2311     raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length
2312   end
2313   uses_cks = opts[:uses_composite_keys] = cks.length > 1
2314   opts[:cartesian_product_number] ||= 0
2315 
2316   if !opts.has_key?(:many_to_one_pk_lookup) &&
2317      (opts[:dataset] || opts[:conditions] || opts[:block] || opts[:select] ||
2318       (opts.has_key?(:key) && opts[:key] == nil))
2319     opts[:many_to_one_pk_lookup] = false
2320   end
2321   auto_assocs = @autoreloading_associations
2322   cks.each do |k|
2323     (auto_assocs[k] ||= []) << name
2324   end
2325 
2326   opts[:dataset] ||= opts.association_dataset_proc
2327   opts[:eager_loader] ||= proc do |eo|
2328     h = eo[:id_map]
2329     pk_meths = opts.primary_key_methods
2330 
2331     eager_load_results(opts, eo) do |assoc_record|
2332       hash_key = uses_cks ? pk_meths.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(opts.primary_key_method)
2333       h[hash_key].each{|object| object.associations[name] = assoc_record}
2334     end
2335   end
2336       
2337   join_type = opts[:graph_join_type]
2338   select = opts[:graph_select]
2339   use_only_conditions = opts.include?(:graph_only_conditions)
2340   only_conditions = opts[:graph_only_conditions]
2341   conditions = opts[:graph_conditions]
2342   graph_block = opts[:graph_block]
2343   graph_cks = opts[:graph_keys]
2344   opts[:eager_grapher] ||= proc do |eo|
2345     ds = eo[:self]
2346     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)
2347   end
2348       
2349   return if opts[:read_only]
2350       
2351   unless opts.has_key?(:setter)
2352     opts[:setter] = proc{|o| cks.zip(opts.primary_key_methods).each{|k, pk| set_column_value(:"#{k}=", (o.get_column_value(pk) if o))}}
2353   end
2354   if opts.fetch(:setter, true)
2355     opts[:_setter] = proc{|o| set_associated_object(opts, o)}
2356   end
2357 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
2481 def def_one_through_one(opts)
2482   def_many_to_many(opts)
2483 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
2360 def def_one_to_many(opts)
2361   one_to_one = opts[:type] == :one_to_one
2362   name = opts[:name]
2363   key = (opts[:key] ||= opts.default_key)
2364   km = opts[:key_method] ||= opts[:key]
2365   cks = opts[:keys] = Array(key)
2366   opts[:key_methods] = Array(opts[:key_method])
2367   primary_key = (opts[:primary_key] ||= self.primary_key)
2368   opts[:eager_loader_key] = primary_key unless opts.has_key?(:eager_loader_key)
2369   cpks = opts[:primary_keys] = Array(primary_key)
2370   pkc = opts[:primary_key_column] ||= primary_key
2371   pkcs = opts[:primary_key_columns] ||= Array(pkc)
2372   raise(Error, "mismatched number of keys: #{cks.inspect} vs #{cpks.inspect}") unless cks.length == cpks.length
2373   uses_cks = opts[:uses_composite_keys] = cks.length > 1
2374   opts[:dataset] ||= opts.association_dataset_proc
2375   opts[:eager_loader] ||= proc do |eo|
2376     h = eo[:id_map]
2377     reciprocal = opts.reciprocal
2378     assign_singular = opts.assign_singular?
2379     delete_rn = opts.delete_row_number_column
2380 
2381     eager_load_results(opts, eo) do |assoc_record|
2382       assoc_record.values.delete(delete_rn) if delete_rn
2383       hash_key = uses_cks ? km.map{|k| assoc_record.get_column_value(k)} : assoc_record.get_column_value(km)
2384       objects = h[hash_key]
2385       if assign_singular
2386         objects.each do |object| 
2387           unless object.associations[name]
2388             object.associations[name] = assoc_record
2389             assoc_record.associations[reciprocal] = object if reciprocal
2390           end
2391         end
2392       else
2393         objects.each do |object| 
2394           object.associations[name].push(assoc_record)
2395           assoc_record.associations[reciprocal] = object if reciprocal
2396         end
2397       end
2398     end
2399   end
2400   
2401   join_type = opts[:graph_join_type]
2402   select = opts[:graph_select]
2403   use_only_conditions = opts.include?(:graph_only_conditions)
2404   only_conditions = opts[:graph_only_conditions]
2405   conditions = opts[:graph_conditions]
2406   opts[:cartesian_product_number] ||= one_to_one ? 0 : 1
2407   graph_block = opts[:graph_block]
2408   opts[:eager_grapher] ||= proc do |eo|
2409     ds = eo[:self]
2410     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)
2411     # We only load reciprocals for one_to_many associations, as other reciprocals don't make sense
2412     ds.opts[:eager_graph][:reciprocals][eo[:table_alias]] = opts.reciprocal
2413     ds
2414   end
2415       
2416   return if opts[:read_only]
2417 
2418   save_opts = {:validate=>opts[:validate]}
2419   ck_nil_hash ={}
2420   cks.each{|k| ck_nil_hash[k] = nil}
2421 
2422   if one_to_one
2423     unless opts.has_key?(:setter)
2424       opts[:setter] = proc do |o|
2425         up_ds = _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)})))
2426 
2427         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)))
2428           if old = up_ds.first
2429             cks.each{|k| old.set_column_value(:"#{k}=", nil)}
2430           end
2431           save_old = true
2432         end
2433 
2434         if o
2435           if !o.new? && !save_old
2436             up_ds = up_ds.exclude(o.pk_hash)
2437           end
2438           cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))}
2439         end
2440 
2441         checked_transaction do
2442           if save_old
2443             old.save(save_opts) || raise(Sequel::Error, "invalid previously associated object, cannot save") if old
2444           else
2445             up_ds.skip_limit_check.update(ck_nil_hash)
2446           end
2447 
2448           o.save(save_opts) || raise(Sequel::Error, "invalid associated object, cannot save") if o
2449         end
2450       end
2451     end
2452     if opts.fetch(:setter, true)
2453       opts[:_setter] = proc{|o| set_one_to_one_associated_object(opts, o)}
2454     end
2455   else 
2456     save_opts[:raise_on_failure] = opts[:raise_on_save_failure] != false
2457 
2458     unless opts.has_key?(:adder)
2459       opts[:adder] = proc do |o|
2460         cks.zip(cpks).each{|k, pk| o.set_column_value(:"#{k}=", get_column_value(pk))}
2461         o.save(save_opts)
2462       end
2463     end
2464     
2465     unless opts.has_key?(:remover)
2466       opts[:remover] = proc do |o|
2467         cks.each{|k| o.set_column_value(:"#{k}=", nil)}
2468         o.save(save_opts)
2469       end
2470     end
2471 
2472     unless opts.has_key?(:clearer)
2473       opts[:clearer] = proc do
2474         _apply_association_options(opts, opts.associated_dataset.where(cks.zip(cpks.map{|k| get_column_value(k)}))).update(ck_nil_hash)
2475       end
2476     end
2477   end
2478 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
2486 def def_one_to_one(opts)
2487   def_one_to_many(opts)
2488 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
2491 def eager_graph_dataset(opts, eager_options)
2492   ds = opts.associated_class.dataset
2493   if opts[:graph_use_association_block] && (b = opts[:block])
2494     ds = b.call(ds)
2495   end
2496   if cb = eager_options[:callback]
2497     ds = cb.call(ds)
2498   end
2499   ds
2500 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
2504 def reload_db_schema?
2505   !@cache_associations
2506 end