drop not null constraint on column `user_id` of tables `profiles` and `user_filters`

synapse/storage/schema/__init__.py

@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-SCHEMA_VERSION = 80  # remember to update the list below when updating
+SCHEMA_VERSION = 81  # remember to update the list below when updating
 """Represents the expectations made by the codebase about the database schema
 
 This should be incremented whenever the codebase changes its requirements on the
@@ -114,6 +114,9 @@ Changes in SCHEMA_VERSION = 79
 Changes in SCHEMA_VERSION = 80
     - The event_txn_id_device_id is always written to for new events.
     - Add tables for the task scheduler.
+
+Changes in SCHEMA_VERSION = 81
+    - We no longer write to column user_id of tables profiles and user_filters
 """
 
 

synapse/storage/schema/main/delta/81/01_drop_user_id_constraint_profiles.py

@@ -0,0 +1,64 @@
+# Copyright 2023 The Matrix.org Foundation C.I.C
+#
+#  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.
+
+from synapse.storage.database import LoggingTransaction
+from synapse.storage.engines import BaseDatabaseEngine, PostgresEngine
+
+
+def run_create(cur: LoggingTransaction, database_engine: BaseDatabaseEngine) -> None:
+    """
+    Update to drop the NOT NULL constraint on column `user_id` so that we can cease to
+    write to it without inserts to other columns triggering the constraint
+    """
+
+    if isinstance(database_engine, PostgresEngine):
+        drop_sql = """
+        ALTER TABLE profiles ALTER COLUMN user_id DROP NOT NULL
+        """
+        cur.execute(drop_sql)
+    else:
+        # irritatingly in SQLite we need to rewrite the table to drop the constraint.
+        cur.execute("DROP TABLE IF EXISTS temp_profiles")
+
+        create_sql = """
+        CREATE TABLE temp_profiles (
+            full_user_id text NOT NULL,
+            user_id text,
+            displayname text,
+            avatar_url text,
+            UNIQUE (full_user_id),
+            UNIQUE (user_id)
+        )
+        """
+        cur.execute(create_sql)
+
+        copy_sql = """
+        INSERT INTO temp_profiles (
+            user_id,
+            displayname,
+            avatar_url,
+            full_user_id)
+            SELECT user_id, displayname, avatar_url, full_user_id FROM profiles
+        """
+        cur.execute(copy_sql)
+
+        drop_sql = """
+        DROP TABLE profiles
+        """
+        cur.execute(drop_sql)
+
+        rename_sql = """
+        ALTER TABLE temp_profiles RENAME to profiles
+        """
+        cur.execute(rename_sql)

synapse/storage/schema/main/delta/81/02_drop_user_id_constraint_user_filters.py

@@ -0,0 +1,68 @@
+# Copyright 2023 The Matrix.org Foundation C.I.C
+#
+#  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.
+
+from synapse.storage.database import LoggingTransaction
+from synapse.storage.engines import BaseDatabaseEngine, PostgresEngine
+
+
+def run_create(cur: LoggingTransaction, database_engine: BaseDatabaseEngine) -> None:
+    """
+    Update to drop the NOT NULL constraint on column user_id so that we can cease to
+    write to it without inserts to other columns triggering the constraint
+    """
+    if isinstance(database_engine, PostgresEngine):
+        drop_sql = """
+        ALTER TABLE user_filters ALTER COLUMN user_id DROP NOT NULL
+        """
+        cur.execute(drop_sql)
+
+    else:
+        # irritatingly in SQLite we need to rewrite the table to drop the constraint.
+        cur.execute("DROP TABLE IF EXISTS temp_user_filters")
+
+        create_sql = """
+        CREATE TABLE temp_user_filters (
+            full_user_id text NOT NULL,
+            user_id text,
+            filter_id bigint NOT NULL,
+            filter_json bytea NOT NULL
+        )
+        """
+        cur.execute(create_sql)
+
+        index_sql = """
+            CREATE UNIQUE INDEX IF NOT EXISTS user_filters_full_user_id_unique ON
+            temp_user_filters (full_user_id, filter_id)
+        """
+        cur.execute(index_sql)
+
+        copy_sql = """
+            INSERT INTO temp_user_filters (
+                user_id,
+                filter_id,
+                filter_json,
+                full_user_id)
+            SELECT user_id, filter_id, filter_json, full_user_id FROM user_filters
+        """
+        cur.execute(copy_sql)
+
+        drop_sql = """
+        DROP TABLE user_filters
+        """
+        cur.execute(drop_sql)
+
+        rename_sql = """
+        ALTER TABLE temp_user_filters RENAME to user_filters
+        """
+        cur.execute(rename_sql)