How to collect statistics in an INTERVAL mode

First Check the old values

SQL> select * from sys.aux_stats$;

Create a new and old Statistics Table

SQL> exec dbms_stats.create_stat_table(ownname=>'SYS',stattab=>'backup_stats');

SQL> exec dbms_stats.create_stat_table(ownname=>'SYS',stattab=>'current_stats');

Save the old Statistics

SQL> exec dbms_stats.export_system_stats(stattab=>'backup_stats');

How to modify Statistics History Retention

Check current retention value

SQL> select dbms_stats.get_stats_history_retention from dual;

GET_STATS_HISTORY_RETENTION

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