module Sequel::Model::Associations::SingularAssociationReflection

Methods that turn an association that returns multiple objects into an association that returns a single object.

Public Instance Methods

assign_singular?() click to toggle source

Singular associations do not assign singular if they are using the ruby eager limit strategy and have a slice range, since they need to store the array of associated objects in order to pick the correct one with an offset.

Calls superclass method

     # File lib/sequel/model/associations.rb
1304 def assign_singular?
1305   super && (eager_limit_strategy != :ruby || !slice_range)
1306 end

filter_by_associations_add_conditions?() click to toggle source

Add conditions when filtering by singular associations with orders, since the underlying relationship is probably not one-to-one.

Calls superclass method

     # File lib/sequel/model/associations.rb
1310 def filter_by_associations_add_conditions?
1311   super || self[:order] || self[:eager_limit_strategy] || self[:filter_limit_strategy]
1312 end

limit_and_offset() click to toggle source

Make sure singular associations always have 1 as the limit

Calls superclass method

     # File lib/sequel/model/associations.rb
1315 def limit_and_offset
1316   r = super
1317   if r.first == 1
1318     r
1319   else
1320     [1, r[1]]
1321   end
1322 end

returns_array?() click to toggle source

Singular associations always return a single object, not an array.

     # File lib/sequel/model/associations.rb
1325 def returns_array?
1326   false
1327 end

Private Instance Methods

default_eager_limit_strategy() click to toggle source

Only use a eager limit strategy by default if there is an offset or an order.

Calls superclass method

     # File lib/sequel/model/associations.rb
1332 def default_eager_limit_strategy
1333   super if self[:order] || offset
1334 end

filter_by_associations_limit_strategy() click to toggle source

Use a strategy for filtering by associations if there is an order or an offset, or a specific limiting strategy has been specified.

Calls superclass method

     # File lib/sequel/model/associations.rb
1338 def filter_by_associations_limit_strategy
1339   super if self[:order] || offset || self[:eager_limit_strategy] || self[:filter_limit_strategy]
1340 end

true_eager_graph_limit_strategy() click to toggle source

Use the DISTINCT ON eager limit strategy for true if the database supports it.

Calls superclass method

     # File lib/sequel/model/associations.rb
1343 def true_eager_graph_limit_strategy
1344   if associated_class.dataset.supports_ordered_distinct_on? && !offset
1345     :distinct_on
1346   else
1347     super
1348   end
1349 end