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
Source
# File lib/sequel/model/associations.rb 1178 def assign_singular? 1179 super && (eager_limit_strategy != :ruby || !slice_range) 1180 end
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.
Source
# File lib/sequel/model/associations.rb 1184 def filter_by_associations_add_conditions? 1185 super || self[:order] || self[:eager_limit_strategy] || self[:filter_limit_strategy] 1186 end
Add conditions when filtering by singular associations with orders, since the underlying relationship is probably not one-to-one.
Source
# File lib/sequel/model/associations.rb 1189 def limit_and_offset 1190 r = super 1191 if r.first == 1 1192 r 1193 else 1194 [1, r[1]] 1195 end 1196 end
Make sure singular associations always have 1 as the limit
Source
# File lib/sequel/model/associations.rb 1199 def returns_array? 1200 false 1201 end
Singular associations always return a single object, not an array.
Private Instance Methods
Source
# File lib/sequel/model/associations.rb 1206 def default_eager_limit_strategy 1207 super if self[:order] || offset 1208 end
Only use a eager limit strategy by default if there is an offset or an order.
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# File lib/sequel/model/associations.rb 1212 def filter_by_associations_limit_strategy 1213 super if self[:order] || offset || self[:eager_limit_strategy] || self[:filter_limit_strategy] 1214 end
Use a strategy for filtering by associations if there is an order or an offset, or a specific limiting strategy has been specified.
Source
# File lib/sequel/model/associations.rb 1217 def true_eager_graph_limit_strategy 1218 if associated_class.dataset.supports_ordered_distinct_on? && !offset 1219 :distinct_on 1220 else 1221 super 1222 end 1223 end
Use the DISTINCT ON eager limit strategy for true if the database supports it.