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 1184 def assign_singular? 1185 super && (eager_limit_strategy != :ruby || !slice_range) 1186 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 1190 def filter_by_associations_add_conditions? 1191 super || self[:order] || self[:eager_limit_strategy] || self[:filter_limit_strategy] 1192 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 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
Make sure singular associations always have 1 as the limit
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# File lib/sequel/model/associations.rb 1205 def returns_array? 1206 false 1207 end
Singular associations always return a single object, not an array.
Private Instance Methods
Source
# File lib/sequel/model/associations.rb 1212 def default_eager_limit_strategy 1213 super if self[:order] || offset 1214 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 1218 def filter_by_associations_limit_strategy 1219 super if self[:order] || offset || self[:eager_limit_strategy] || self[:filter_limit_strategy] 1220 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 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
Use the DISTINCT ON eager limit strategy for true if the database supports it.