Revert "Merge pull request #10566 from neerajdotname/10509d"

This reverts commit 2b817a5e89ac0e7aeb894a40ae7151a0cf3cef16, reversing
changes made to 353a398bee68c5ea99d76ac7601de0a5fef6f4a5.

Conflicts:
	activerecord/CHANGELOG.md

Reason: the build broke

3 files changed, 1 insertions, 25 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 933ac9fa6c..87167d0529 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -9,22 +9,6 @@
 
     *Neeraj Singh*
 
-*   Do not load all child records for inverse case.
-
-    currently `post.comments.find(Comment.first.id)` would load all
-    comments for the given post to set the inverse association.
-
-    This has a huge performance penalty. Because if post has 100k
-    records and all these 100k records would be loaded in memory
-    even though the comment id was supplied.
-
-    Fix is to use in-memory records only if loaded? is true. Otherwise
-    load the records using full sql.
-
-    Fixes #10509.
-
-    *Neeraj Singh*
-
 *   Fixture setup does no longer depend on `ActiveRecord::Base.configurations`.
     This is relevant when `ENV["DATABASE_URL"]` is used in place of a `database.yml`.
 
diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index 9833822f8f..efd7ecb97c 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -81,7 +81,7 @@ module ActiveRecord
         else
           if options[:finder_sql]
             find_by_scan(*args)
-          elsif options[:inverse_of] && loaded?
+          elsif options[:inverse_of]
             args = args.flatten
             raise RecordNotFound, "Couldn't find #{scope.klass.name} without an ID" if args.blank?
 
diff --git a/activerecord/test/cases/associations/inverse_associations_test.rb b/activerecord/test/cases/associations/inverse_associations_test.rb
index 993e7294cf..b1f0be3204 100644
--- a/activerecord/test/cases/associations/inverse_associations_test.rb
+++ b/activerecord/test/cases/associations/inverse_associations_test.rb
@@ -401,14 +401,6 @@ class InverseHasManyTests < ActiveRecord::TestCase
     assert_equal man.name, man.interests.find(interest.id).man.name, "The name of the man should match after the child name is changed"
   end
 
-  def test_find_on_child_instance_with_id_should_not_load_all_child_records
-    man = Man.create!
-    interest = Interest.create!(man: man)
-
-    man.interests.find(interest.id)
-    refute man.interests.loaded?
-  end
-
   def test_raise_record_not_found_error_when_invalid_ids_are_passed
     man = Man.create!