Revert "Perf: Don't load the association for #delete_all."

This reverts commit b98d1e21635d8776de8893cc09bd86c71f6c78f0.

Closes #6609

Conflicts:

	activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb

4 files changed, 9 insertions, 33 deletions

diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index 4c58094cfd..8ef6b594fd 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -154,7 +154,7 @@ module ActiveRecord
       #
       # See delete for more info.
       def delete_all
-        delete(:all).tap do
+        delete(load_target).tap do
           reset
           loaded!
         end
@@ -226,17 +226,7 @@ module ActiveRecord
       # are actually removed from the database, that depends precisely on
       # +delete_records+. They are in any case removed from the collection.
       def delete(*records)
-        dependent = options[:dependent]
-
-        if records.first == :all
-          if loaded? || dependent == :destroy
-            delete_or_destroy(load_target, dependent)
-          else
-            delete_records(:all, dependent)
-          end
-        else
-          delete_or_destroy(records, dependent)
-        end
+        delete_or_destroy(records, options[:dependent])
       end
 
       # Destroy +records+ and remove them from this association calling
diff --git a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
index e5da0d585c..8c6821323f 100644
--- a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
@@ -47,17 +47,11 @@ module ActiveRecord
             records = load_target if records == :all
             records.each { |record| owner.connection.delete(interpolate(sql, record)) }
           else
-            relation  = join_table
-            condition = relation[reflection.foreign_key].eq(owner.id)
-
-            unless records == :all
-              condition = condition.and(
-                relation[reflection.association_foreign_key].
-                  in(records.map { |x| x.id }.compact)
-              )
-            end
-
-            owner.connection.delete(relation.where(condition).compile_delete)
+            relation = join_table
+            stmt = relation.where(relation[reflection.foreign_key].eq(owner.id).
+              and(relation[reflection.association_foreign_key].in(records.map { |x| x.id }.compact))
+            ).compile_delete
+            owner.connection.delete stmt
           end
         end
 
diff --git a/activerecord/lib/active_record/associations/has_many_association.rb b/activerecord/lib/active_record/associations/has_many_association.rb
index e631579087..059e6c77bc 100644
--- a/activerecord/lib/active_record/associations/has_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_association.rb
@@ -89,12 +89,8 @@ module ActiveRecord
             records.each { |r| r.destroy }
             update_counter(-records.length) unless inverse_updates_counter_cache?
           else
-            if records == :all
-              scope = scoped
-            else
-              keys  = records.map { |r| r[reflection.association_primary_key] }
-              scope = scoped.where(reflection.association_primary_key => keys)
-            end
+            keys  = records.map { |r| r[reflection.association_primary_key] }
+            scope = scoped.where(reflection.association_primary_key => keys)
 
             if method == :delete_all
               update_counter(-scope.delete_all)
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 86c665b5fe..53d49fef2e 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -126,10 +126,6 @@ module ActiveRecord
         def delete_records(records, method)
           ensure_not_nested
 
-          # This is unoptimised; it will load all the target records
-          # even when we just want to delete everything.
-          records = load_target if records == :all
-
           scope = through_association.scoped.where(construct_join_attributes(*records))
 
           case method