Split up device_lists_outbound_pokes table for faster updates.

synapse/storage/schema/delta/42/device_list_last_id.sql

@@ -0,0 +1,33 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * 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.
+ */
+
+
+-- Table of last stream_id that we sent to destination for user_id. This is
+-- used to fill out the `prev_id` fields of outbound device list updates.
+CREATE TABLE device_lists_outbound_last_success (
+    destination TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    stream_id BIGINT NOT NULL
+);
+
+INSERT INTO device_lists_outbound_last_success
+    SELECT destination, user_id, coalesce(max(stream_id), 0) as stream_id
+        FROM device_lists_outbound_pokes
+        WHERE sent = (1 = 1)  -- sqlite doesn't have inbuilt boolean values
+        GROUP BY destination, user_id;
+
+CREATE INDEX device_lists_outbound_last_success_idx ON device_lists_outbound_last_success(
+    destination, user_id, stream_id
+);