Hi,
I use command "db.test.getShardDistribution() " to query data chunks imformation of shards,but there is no some imformation with error. See the "repair before.png".
Then,I use command "db.repairDatabase()" to repair the test database,and use "db.test.getShardDistribution() " to view again.While,there is one shard whose data has lost.See the "repair later.png".

So,what cause the command "db.test.getShardDistribution()" error?
And,whether the command "db.repairDatabase()" is always cause data loss?