DDL logging Parameter in Oracle 11g & 12c
- 1. ======================================================= DDL logging: In Oracle 11g&12c ================================================================ There was no direct option available to log the DDL action in the previous releases. 1) From 11gr2 /12cR1, you can now log the DDL action into xml and log files. 2) This will be very useful to know when the drop or create command was executed and by who. 3) The ENABLE_DDL_LOGGING initiation parameter can be set at the Database or Session levels. 4) When this parameter is enabled, all DDL commands are logged in an xml and a log file under the $ORACLE_BASE/diag/rdbms/DBNAME/log|ddl location. 5) An xml file contains information, such as DDL command, IP address, timestamp etc. 6) It helps to identify User/Table dropped (or) DDL statement is triggered. To enable DDL logging SQL> ALTER SYSTEM|SESSION SET ENABLE_DDL_LOGGING=TRUE; Note: When ENABLE_DDL_LOGGING is set to true, the following DDL statements are written to the alert log: ALTER/CREATE/DROP/TRUNCATE CLUSTER ALTER/CREATE/DROP FUNCTION ALTER/CREATE/DROP INDEX ALTER/CREATE/DROP OUTLINE ALTER/CREATE/DROP PACKAGE ALTER/CREATE/DROP PACKAGE BODY ALTER/CREATE/DROP PROCEDURE ALTER/CREATE/DROP PROFILE ALTER/CREATE/DROP SEQUENCE CREATE/DROP SYNONYM ALTER/CREATE/DROP/RENAME/TRUNCATE TABLE ALTER/CREATE/DROP TRIGGER ALTER/CREATE/DROP TYPE ALTER/CREATE/DROP TYPE BODY DROP USER ALTER/CREATE/DROP VIEW
- 2. Following is the example of DDL logging: ====================================== -bash-4.1$ sqlplus / as sysdba SQL*Plus: Release 12.1.0.2.0 Production on Tue Jun 7 11:26:27 2019 Copyright (c) 1982, 2014, Oracle. All rights reserved. Connected to: Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options SQL> show parameter enable_ddl_logging NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ enable_ddl_logging boolean FALSE ================================================================ Difference Between 11g & 12c for enable_ddl_logging Parameter: ================================================================ In Oracle 11g: DDL statements are written to the alert log in: $ADR_BASE/diag/rdbms/${DBNAME}/${ORACLE_SID}/trace/alert_${ORACLE_SID}.log 1. License: The init.ora parameter ENABLE_DDL_LOGGING is licensed as part of the Database Lifecycle Management Pack when set to TRUE. When set to TRUE, the database reports schema changes in real time into the database alert log under the message group schema_ddl. The default setting is FALSE.” 2. RENAME: was not logged and a bug was reported for that and the same is fixed in 11.2.0.4. Document 12938609.8 – ENABLE_DDL_LOGGING does not log RENAME table statements, this is fixed in 11.2.0.4 However, the feature does not log DDLs of some DBMS_STATS operations like: set_column_stats set_index_stats create_extended_stats drop_extended_stats set_*_prefs (table/schema/global etc) delete_pending_stats publish_pending_stats export_pending_stats create_stat_table
- 3. In Oracle 12c: Now if you look in the following text file: $ADR_BASE/diag/rdbms/${DBNAME}/${ORACLE_SID}/log/ddl_${ORACLE_SID}.log 1. If ENABLE_DDL_LOGGING is enabled, then DDL records are written to the ADR. 2. All DDL operations like alter/create/drop/truncate objects. 3. Only drop user will be logged, But create user will not be. How to ENABLE : SQL> alter system set enable_ddl_logging=true; System altered. SQL> show parameter enable_ddl_logging; NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ enable_ddl_logging boolean TRUE How to DISABLE : SQL> show parameter enable_ddl_logging NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ enable_ddl_logging boolean TRUE SQL> alter system set enable_ddl_logging =FALSE; System altered. SQL> show parameter ENABLE_DDL_LOGGING NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ enable_ddl_logging boolean FALSE SQL> conn syed/syed Connected. SQL> create table Testddl (id number, name varchar2(50)); Table created. SQL> alter table Testddl add ( address varchar2(100)); Table altered.
- 4. SQL> insert into Testddl values (1,'CBT','XYZ'); 1 row created. SQL> commit; Commit complete. SQL> drop table ddltest; Table dropped. Note: Now, check the log file for all DDL commands that was run by user. -bash-4.1$ pwd /mnt/Oracle/diag/rdbms/orclnew/orclnew/log/ddl -bash-4.1$ cat log.xml msg_id='opiexe:4383:2946163730' type='UNKNOWN' group='diag_adl' level='16' host_id='OraLinuxNode' host_addr='10.184.150.107' version='1'> create table Testddl (id number, name varchar2(50)) msg_id='opiexe:4383:2946163730' type='UNKNOWN' group='diag_adl' level='16' host_id='OraLinuxNode' host_addr='10.184.150.107'> alter table Testddl add ( address varchar2(100)) msg_id='opiexe:4383:2946163730' type='UNKNOWN' group='diag_adl' level='16' host_id='OraLinuxNode' host_addr='10.184.150.107'> drop table Testddl ======================================================= THANK YOU ======================================================= Written by: Syed Sadath Ullah M.Tech;OCP Database Administrator Email:oraclecloud777@gmail.com