```
2021-07-13 02:27:57,810 - synapse.handlers.federation - 1248 - ERROR - GET-4 - Failed to backfill from hs1 because NOT NULL constraint failed: event_to_state_groups.state_group
Traceback (most recent call last):
File "/usr/local/lib/python3.8/site-packages/synapse/handlers/federation.py", line 1216, in try_backfill
await self.backfill(
File "/usr/local/lib/python3.8/site-packages/synapse/handlers/federation.py", line 1035, in backfill
await self._auth_and_persist_event(dest, event, context, backfilled=True)
File "/usr/local/lib/python3.8/site-packages/synapse/handlers/federation.py", line 2222, in _auth_and_persist_event
await self._run_push_actions_and_persist_event(event, context, backfilled)
File "/usr/local/lib/python3.8/site-packages/synapse/handlers/federation.py", line 2244, in _run_push_actions_and_persist_event
await self.persist_events_and_notify(
File "/usr/local/lib/python3.8/site-packages/synapse/handlers/federation.py", line 3290, in persist_events_and_notify
events, max_stream_token = await self.storage.persistence.persist_events(
File "/usr/local/lib/python3.8/site-packages/synapse/logging/opentracing.py", line 774, in _trace_inner
return await func(*args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/persist_events.py", line 320, in persist_events
ret_vals = await yieldable_gather_results(enqueue, partitioned.items())
File "/usr/local/lib/python3.8/site-packages/synapse/storage/persist_events.py", line 237, in handle_queue_loop
ret = await self._per_item_callback(
File "/usr/local/lib/python3.8/site-packages/synapse/storage/persist_events.py", line 577, in _persist_event_batch
await self.persist_events_store._persist_events_and_state_updates(
File "/usr/local/lib/python3.8/site-packages/synapse/storage/databases/main/events.py", line 176, in _persist_events_and_state_updates
await self.db_pool.runInteraction(
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 681, in runInteraction
result = await self.runWithConnection(
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 770, in runWithConnection
return await make_deferred_yieldable(
File "/usr/local/lib/python3.8/site-packages/twisted/python/threadpool.py", line 238, in inContext
result = inContext.theWork() # type: ignore[attr-defined]
File "/usr/local/lib/python3.8/site-packages/twisted/python/threadpool.py", line 254, in <lambda>
inContext.theWork = lambda: context.call( # type: ignore[attr-defined]
File "/usr/local/lib/python3.8/site-packages/twisted/python/context.py", line 118, in callWithContext
return self.currentContext().callWithContext(ctx, func, *args, **kw)
File "/usr/local/lib/python3.8/site-packages/twisted/python/context.py", line 83, in callWithContext
return func(*args, **kw)
File "/usr/local/lib/python3.8/site-packages/twisted/enterprise/adbapi.py", line 293, in _runWithConnection
compat.reraise(excValue, excTraceback)
File "/usr/local/lib/python3.8/site-packages/twisted/python/deprecate.py", line 298, in deprecatedFunction
return function(*args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/twisted/python/compat.py", line 403, in reraise
raise exception.with_traceback(traceback)
File "/usr/local/lib/python3.8/site-packages/twisted/enterprise/adbapi.py", line 284, in _runWithConnection
result = func(conn, *args, **kw)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 765, in inner_func
return func(db_conn, *args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 549, in new_transaction
r = func(cursor, *args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/synapse/logging/utils.py", line 69, in wrapped
return f(*args, **kwargs)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/databases/main/events.py", line 385, in _persist_events_txn
self._store_event_state_mappings_txn(txn, events_and_contexts)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/databases/main/events.py", line 2065, in _store_event_state_mappings_txn
self.db_pool.simple_insert_many_txn(
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 923, in simple_insert_many_txn
txn.execute_batch(sql, vals)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 280, in execute_batch
self.executemany(sql, args)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 300, in executemany
self._do_execute(self.txn.executemany, sql, *args)
File "/usr/local/lib/python3.8/site-packages/synapse/storage/database.py", line 330, in _do_execute
return func(sql, *args)
sqlite3.IntegrityError: NOT NULL constraint failed: event_to_state_groups.state_group
```