diff --git a/internal/matrix/store.go b/internal/matrix/store.go
index 3d07674..1bc6f49 100644
--- a/internal/matrix/store.go
+++ b/internal/matrix/store.go
@@ -35,7 +35,7 @@ func (s sqlStore) CreateTables() error {
 			room_id	TEXT,
 			user_id	TEXT,
 
-			PRIMARY KEY (room_id, user_id)
+			PRIMARY KEY (room_id, user_id) ON CONFLICT IGNORE
 		);
 		`,
 	}