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
1157 def assign_singular?
1158   super && (eager_limit_strategy != :ruby || !slice_range)
1159 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
1163 def filter_by_associations_add_conditions?
1164   super || self[:order] || self[:eager_limit_strategy] || self[:filter_limit_strategy]
1165 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
1168 def limit_and_offset
1169   r = super
1170   if r.first == 1
1171     r
1172   else
1173     [1, r[1]]
1174   end
1175 end
returns_array?() click to toggle source

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

     # File lib/sequel/model/associations.rb
1178 def returns_array?
1179   false
1180 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
1185 def default_eager_limit_strategy
1186   super if self[:order] || offset
1187 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
1191 def filter_by_associations_limit_strategy
1192   super if self[:order] || offset || self[:eager_limit_strategy] || self[:filter_limit_strategy]
1193 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
1196 def true_eager_graph_limit_strategy
1197   if associated_class.dataset.supports_ordered_distinct_on? && !offset
1198     :distinct_on
1199   else
1200     super
1201   end
1202 end