USER_TAB_MODIFICATIONS describes modiﬁcations to all tables owned by the current user that have been modiﬁed since the last time statistics were gathered on the tables. 使用User_tab_modifications来获取数据表的DML过程： 1，SQL> select * from USER_TAB_MODIFICATIONS ; no rows selected 2, SQL>insert into test values(1,'Asher'); one row inserted 3, SQL>select * from USER_TAB_MODIFICATIONS ; no rows selected Why? just waiting for a moment,or after I've executed the procedure【dbms_stats.flush_database_monitoring_info()】，we will get the expected result. 4, SQL> exec dbms_stats.flush_database_monitoring_info(); PL/SQL procedure successfully completed. 5,SQL> select * from USER_TAB_MODIFICATIONS ; The correct result will appears.