Add receipts event stream ordering

changelog.d/13703.misc

@@ -0,0 +1 @@
+Add & populate `event_stream_ordering` column on receipts table for future optimisation of push action processing. Contributed by Nick @ Beeper (@fizzadar).

synapse/storage/databases/main/receipts.py

@@ -664,6 +664,14 @@ def _insert_linearized_receipt_txn(
             self._receipts_stream_cache.entity_has_changed, room_id, stream_id
         )
 
+        upsert_values: Dict[str, Any] = {
+            "stream_id": stream_id,
+            "event_id": event_id,
+            "data": json_encoder.encode(data),
+        }
+        if stream_ordering is not None:
+            upsert_values["event_stream_ordering"] = stream_ordering
+
         self.db_pool.simple_upsert_txn(
             txn,
             table="receipts_linearized",
@@ -672,11 +680,7 @@ def _insert_linearized_receipt_txn(
                 "receipt_type": receipt_type,
                 "user_id": user_id,
             },
-            values={
-                "stream_id": stream_id,
-                "event_id": event_id,
-                "data": json_encoder.encode(data),
-            },
+            values=upsert_values,
             # receipts_linearized has a unique constraint on
             # (user_id, room_id, receipt_type), so no need to lock
             lock=False,

synapse/storage/schema/main/delta/72/05receipts_event_stream_ordering.sql

@@ -0,0 +1,16 @@
+/* Copyright 2022 Beeper
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE receipts_linearized ADD COLUMN event_stream_ordering integer;