diff options
Diffstat (limited to 'synapse/storage/util')
| -rw-r--r-- | synapse/storage/util/id_generators.py | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/synapse/storage/util/id_generators.py b/synapse/storage/util/id_generators.py index 727fcc521c..4269eaf918 100644 --- a/synapse/storage/util/id_generators.py +++ b/synapse/storage/util/id_generators.py @@ -287,8 +287,12 @@ class MultiWriterIdGenerator: min_stream_id = min(self._current_positions.values(), default=None) if min_stream_id is None: + # We add a GREATEST here to ensure that the result is always + # positive. (This can be a problem for e.g. backfill streams where + # the server has never backfilled). sql = """ - SELECT COALESCE(%(agg)s(%(id)s), 1) FROM %(table)s + SELECT GREATEST(COALESCE(%(agg)s(%(id)s), 1), 1) + FROM %(table)s """ % { "id": id_column, "table": table, |