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
1184 def assign_singular?
1185   super && (eager_limit_strategy != :ruby || !slice_range)
1186 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
1190 def filter_by_associations_add_conditions?
1191   super || self[:order] || self[:eager_limit_strategy] || self[:filter_limit_strategy]
1192 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
1195 def limit_and_offset
1196   r = super
1197   if r.first == 1
1198     r
1199   else
1200     [1, r[1]]
1201   end
1202 end
returns_array?() click to toggle source

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

     # File lib/sequel/model/associations.rb
1205 def returns_array?
1206   false
1207 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
1212 def default_eager_limit_strategy
1213   super if self[:order] || offset
1214 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
1218 def filter_by_associations_limit_strategy
1219   super if self[:order] || offset || self[:eager_limit_strategy] || self[:filter_limit_strategy]
1220 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
1223 def true_eager_graph_limit_strategy
1224   if associated_class.dataset.supports_ordered_distinct_on? && !offset
1225     :distinct_on
1226   else
1227     super
1228   end
1229 end