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1 files changed, 1 insertions, 1 deletions

diff --git a/synapse/storage/schema/delta/42/user_dir.py b/synapse/storage/schema/delta/42/user_dir.py

index 38538960a4..57b89ba552 100644
--- a/synapse/storage/schema/delta/42/user_dir.py
+++ b/synapse/storage/schema/delta/42/user_dir.py
@@ -34,7 +34,7 @@ INSERT INTO user_directory_stream_pos (stream_id) VALUES (null);
 POSTGRES_TABLE = """
 CREATE TABLE user_directory (
     user_id TEXT NOT NULL,
-    room_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,  -- A room_id that we know is public
     display_name TEXT,
     avatar_url TEXT,
     vector tsvector