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
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.
# File lib/sequel/model/associations.rb 1157 def assign_singular? 1158 super && (eager_limit_strategy != :ruby || !slice_range) 1159 end
Add conditions when filtering by singular associations with orders, since the underlying relationship is probably not one-to-one.
# 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
Make sure singular associations always have 1 as the limit
# 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
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
Only use a eager limit strategy by default if there is an offset or an order.
# File lib/sequel/model/associations.rb 1185 def default_eager_limit_strategy 1186 super if self[:order] || offset 1187 end
Use a strategy for filtering by associations if there is an order or an offset, or a specific limiting strategy has been specified.
# 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
Use the DISTINCT ON eager limit strategy for true if the database supports it.
# 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