BR does not back up statistics (except in v4.0.9). Therefore, after restoring the backup data, you need to manually execute
ANALYZE TABLE or wait for TiDB to automatically execute
In v4.0.9, BR backs up statistics by default, which consumes too much memory. To ensure that the backup process goes well, the backup for statistics is disabled by default starting from v4.0.10.
If you do not execute
ANALYZE on the table, TiDB will fail to select the optimal execution plan due to inaccurate statistics. If query performance is not a key concern, you can ignore