Updating row changes

If a large number of rows are added to or deleted from an object at the data source, the federated database is not aware of these changes because the catalog statistics for the nickname continue to indicate the old number of rows.

However you might notice degradation in performance because the optimizer continues to make decisions based on nickname statistics information that is no longer accurate. After updating statistics for the remote object at the data source, you can update the statistics for the nickname to ensure that the optimizer can use accurate statistics when it generates and chooses access plans for processing queries on the data source.