Database Trigger for Capturing all DDL Commands and Storing into a TABLE
Step 1:
First create a table:

CREATE TABLE ddl_log (
OS_USER VARCHAR2(30),
user_name VARCHAR2(30),
ddl_date DATE,
ddl_type VARCHAR2(30),
object_type VARCHAR2(18),
owner VARCHAR2(30),
object_name VARCHAR2(128),
statement varchar2(4000));


Step 2:

Then Create the following trigger, it will automatically capture the statement and then will insert into above table..

CREATE OR REPLACE TRIGGER DDL_AUDITING
AFTER DDL ON DATABASE
DECLARE
sql_text ora_name_list_t;
v_stmt long;
n number;
BEGIN
n := ora_sql_txt(sql_text);
FOR i IN 1..n
LOOP
v_stmt := v_stmt || sql_text(i);
END LOOP;
INSERT INTO ddl_log
(os_user,
user_name, ddl_date, ddl_type,
object_type, owner,
object_name,STATEMENT)
VALUES
(sys_context(\'USERENV\',\'OS_USER\'),ora_login_user, SYSDATE, ora_sysevent,
ora_dict_obj_type, ora_dict_obj_owner,
ora_dict_obj_name,v_stmt);
END DDL_AUDITING;

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