Prefer includes over preload

ruby_event_store-active_record/lib/ruby_event_store/active_record/event_repository_reader.rb

@@ -96,7 +96,7 @@ def read_scope(spec)
           stream = stream.where(newer_than_or_equal_condition(spec)) if spec.newer_than_or_equal
           stream.order(id: order(spec))
         else
-          stream = @stream_klass.preload(:event).where(stream: spec.stream.name)
+          stream = @stream_klass.includes(:event).where(stream: spec.stream.name)
           stream = stream.where(event_id: spec.with_ids) if spec.with_ids?
           stream = stream.joins(:event).where(@event_klass.table_name => { event_type: spec.with_types }) if spec.with_types?
           stream = stream.joins(:event).order(as_at(spec)) if spec.time_sort_by_as_at?

ruby_event_store-active_record/spec/event_repository_spec.rb

@@ -10,7 +10,6 @@ module ActiveRecord
 
       it_behaves_like :event_repository, mk_repository, helper
 
-
       let(:repository) { mk_repository.call }
       let(:specification) do
         Specification.new(
@@ -277,6 +276,47 @@ module ActiveRecord
         }x
       end
 
+      specify 'inner join events when event filtering criteria present' do
+        [
+          specification.stream("stream").of_type("type"),
+          specification.stream("stream").as_of,
+          specification.stream("stream").as_at,
+          specification.stream("stream").older_than(Time.now),
+          specification.stream("stream").older_than_or_equal(Time.now),
+          specification.stream("stream").newer_than(Time.now),
+          specification.stream("stream").newer_than_or_equal(Time.now),
+        ].each do |spec|
+          expect {
+            repository.read(spec.result).to_a
+          }.to match_query /INNER\s+JOIN\s+.event_store_events./
+        end
+      end
+
+      specify "avoid N+1 without additional query when join is used for querying" do
+        repository.append_to_stream(
+          [SRecord.new, SRecord.new],
+          Stream.new("stream"),
+          ExpectedVersion.auto
+        )
+        expect { repository.read(specification.stream("stream").of_type("type").result) }.to match_query_count(1)
+        expect { repository.read(specification.stream("stream").as_of.result) }.to match_query_count(1)
+        expect { repository.read(specification.stream("stream").as_at.result) }.to match_query_count(1)
+        expect { repository.read(specification.stream("stream").older_than(Time.now).result) }.to match_query_count(1)
+        expect { repository.read(specification.stream("stream").older_than_or_equal(Time.now).result) }.to match_query_count(1)
+        expect { repository.read(specification.stream("stream").newer_than(Time.now).result) }.to match_query_count(1)
+        expect { repository.read(specification.stream("stream").newer_than_or_equal(Time.now).result) }.to match_query_count(1)
+      end
+
+      specify "don't join events when no event filtering criteria when counting" do
+        expect {
+          repository.count(specification.stream("stream").result)
+        }.to match_query %r{
+          SELECT\s+COUNT\(\*\)\s+
+          FROM\s+.event_store_events_in_streams.\s+
+          WHERE\s+.event_store_events_in_streams.\..stream.\s+=\s+(\?|\$1|'stream')
+        }x
+      end
+
       private
 
       def with_precision(time)