Oracle Solution for Error ora-13711

ORA-13711: Some snapshots in the range [string, string] are missing key statistics.

What triggered the Error:

Some AWR tables encountered errors while creating one or more snapshots in the given range. The data present in one or more of these missing tables is necessary to perform an ADDM analysis.

What should we do to fix it:

Look in DBA_HIST_SNAP_ERROR to find what tables are missing in the given snapshot range. Use the ERROR_NUMBER column in that view together with the alert log to identify the reason for failure and take necessary action to prevent such failures in the future. Try running ADDM on a different snapshot range that does not include any incomplete snapshots.