diff options
Diffstat (limited to 'activerecord/lib/active_record/association_preload.rb')
| -rw-r--r-- | activerecord/lib/active_record/association_preload.rb | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/activerecord/lib/active_record/association_preload.rb b/activerecord/lib/active_record/association_preload.rb index 3e7c787dee..da4ebdef51 100644 --- a/activerecord/lib/active_record/association_preload.rb +++ b/activerecord/lib/active_record/association_preload.rb @@ -65,7 +65,13 @@ module ActiveRecord end def set_association_single_records(id_to_record_map, reflection_name, associated_records, key) + seen_keys = {} associated_records.each do |associated_record| + #this is a has_one or belongs_to: there should only be one record. + #Unfortunately we can't (in portable way) ask the database for 'all records where foo_id in (x,y,z), but please + # only one row per distinct foo_id' so this where we enforce that + next if seen_keys[associated_record[key].to_s] + seen_keys[associated_record[key].to_s] = true mapped_records = id_to_record_map[associated_record[key].to_s] mapped_records.each do |mapped_record| mapped_record.send("set_#{reflection_name}_target", associated_record) @@ -122,7 +128,6 @@ module ActiveRecord else records.each {|record| record.send("set_#{reflection.name}_target", nil)} - set_association_single_records(id_to_record_map, reflection.name, find_associated_records(ids, reflection, preload_options), reflection.primary_key_name) end end |