Oracle Database Discussions

Hi All,

I am in the process of setting up gathering of schema statistics on my database and was trying to setup estimate stale statistics based on the data from the USER_TAB_MODIFICATONS table. Although I see that monitoring has been turned ON for all the tables in the DB and DML operations are also being carried out on a daily basis, the USER_TAB_MODIFICATIONS remains empty all the time.

I tried executing DBMS_STATS.FLUSH_DB_MONITORING_INFO so as to get this table populated. As soon as i executed it, i could see that the records for all the transactions carried out on that schema during the day appeared in the USER_TAB_MODIFICATIONS table. However, when i again carried out a DML operation as waited for 3 hrs so that it would get populated automatically in the table, I could not see any rows for that table in user_tab_modifications.

Can anyone help me out with what could possibly be the reason behind it? Maybe some background process that populated the user_tab_modifications every 3 hours is disabled? Or is there any other reason behind it?

Please advice.