Sunday, December 31, 2023

Webinar: Oracle Database 23c Security new features

This Webinar helps you to understand Oracle Database 23c Security new features and head start using these features

Date and time: Jan 8th 2024, 8:00am-9:00am
Pacific Daylight Time (San Francisco, GMT-07:00)

This Webinar covers following Topics.
  • SQL Firewall
  • Audit
  • Authentication
  • Authorization
  • Encryption
  • Autonomous Database
  • OtherT
To register for this Webinar, please send an email to SatishbabuGunukula@gmail.com
You will receive an email confirmation with meeting link or Webinar link will be posted here.

Note that registrations are limited and first come and first serve basis.

For presentation link Click here

Thanks & Regards,
http://www.oracleracexpert.com

Thursday, November 9, 2023

ORA-29861: domain index is marked LOADING/FAILED/UNUSABLE

When users performing the transactions on tables where DOMAIN,SPATIAL indexes are part of it they may receive below error and unable to proceed.

SQL> DELETE FROM USER_URL where CXT_ID=8484884;
ERROR at line 1: ORA-29861: domain index is marked LOADING/FAILED/UNUSABLE

The main reason for this error is user might have copied the table/index using export/import or different method but the CREATE INDEX and failed.

Find out what caused the failure of CREATE INDEX. In many cases not having enough space on the Tablespace where you are creating the index is the culprit.

SQL> SELECT INDEX_NAME, TABLE_NAME STATUS,DOMIDX_STATUS,DOMIDX_OPSTATUS FROM DBA_INDEXES WHERE DOMIDX_OPSTATUS='FAILED';

INDEX_NAME     TABLE_NAME STATUS   DOMIDX_STATUS  DOMIDX_OPSTATUS
------------------ --------------- ---------- --------------------- -------------------------  
USER_URL_IDX  USER_URL      VALID    VALID                    FAILED


When verified I found that schema refreshed recently, and index not created successfully.

ORA-31693: Table data object "FIN"."USER_URL" failed to load/unload and is being skipped due to error:
ORA-29861: domain index is marked LOADING/FAILED/UNUSABLE

If you need workaround to proceed with transactions immediately, then drop the index.
The permanent fix will be drop and recreate index successfully.

To avoid this type of issues, make sure you perform following checks.

1. Before refresh verify the tablespace or file systems has enough space and add required space
2. After import check the data pump or import log file and fix all failures
3. Run utlrp.sql to recompile all invalid objects.

Thanks & Regards


Friday, October 20, 2023

Oracle "Hyperion EPMA Server" service is not coming online

Recently I have encountered this issue with Oracle Hyperion. When we restarted Hyperion server, the “Hyperion EPMA Server” service is not coming online and application is down.

Here are the Errors from event.log

EPMA_Server
[EPMA Server Startup] ERROR SVR_ERR_PROCESSMGR_CANT_INIT_SESSIONMGR:Cannot initialize the Session Manager.Hyperion.DimensionServer.Interface.Exceptions.EPMAServiceException: Cannot initialize the Session Manager. ---> Hyperion.CommonServices.Exceptions.SessionManagerException: An error was encountered by the CAS Security Provider: Class: java.lang.NullPointerException
StackTrace:

at Hyperion.DimensionServer.SessionManager.CasSecurityProvider.GetDataBaseDetails(String& vendor, String& serverName, Int32& dbPort, String& dbName, String& username, String& password, String& jdbcUrl)
at Hyperion.DimensionServer.SessionManager.SessionManager.InitializeSqlConnectionString()
at Hyperion.DimensionServer.SessionManager.SessionManager.Initialize(String configFileName, Boolean restorePastInstanceSessions, Boolean enableCaching)
--- End of inner exception stack trace ---


Hyperion EPMA DimmensionServer
Service cannot be started. Hyperion.DimensionServer.Interface.Exceptions.EPMAServiceException: Cannot initialize the Session Manager. ---> Hyperion.CommonServices.Exceptions.SessionManagerException: An error was encountered by the CAS Security Provider: Class: java.lang.NullPointerException
StackTrace:
at Hyperion.DimensionServer.SessionManager.CasSecurityProvider.GetDataBaseDetails(String& vendor, String& serverName, Int32& dbPort, String& dbName, String& username, String& password, String& jdbcUrl)
at Hyperion.DimensionServer.SessionManager.SessionManager.InitializeSqlConnectionString()
at Hyperion.DimensionServer.SessionManager.SessionManager.Initialize(String configFileName, Boolean restorePastInstanceSessions, Boolean enableCaching)
--- End of inner exception stack trace ---

The event log is no much helpful. But note that the Hyperion EPMA Service will not come up if you have any issues with database. Check the logs to see any “ORA- “errors .

I found below error in EssbaseAdminServices0.log
#### <[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'> <> <> <> <1329242417925> ORA-28001: the password has expired

Now it’s clear that Database user password expired.

SQL> select USERNAME, ACCOUNT_STATUS from dba_users where USERNAME = ‘SHARED_SERVICES’;

USERNAME ACCOUNT_STATUS
------------------------------ --------------------------------
SHARED_SERVICES EXPIRED(GRACE)

Do not change the password. If you change the password then you need to re-configure the Hyperion service in order to use the new password.

If you know the password then set the using below command.
SQL> Alter user SHARED_SERVICES identified by ‘xxxxxx’;

If you don’t know the password then reset the password following below steps
SQL> select password from sys.user$ where name='SHARED_SERVICES';

PASSWORD
------------------------------
61266722B44D5BG418

SQL> alter user QWERTY identified by values '61266722B44D5BG418’;
User altered.

Also make sure to modify PASSWORD_LIFE_TIME to “UNLIMITED” for DEFAULT or User profile that you are using

SQL> alter profile default limit PASSWORD_LIFE_TIME unlimited;
Profile altered.

Regards,
Satishbabu Gunukula
http://www.oracleracexpert.com

ORA-02304: invalid object identifier literal and ORA-39083 errors during impdp

Users might receive below error during the import.

ORA-39083: Object type TYPE:"ORCL"."OID_TAB1" failed to create with error:
ORA-02304: invalid object identifier literal


Failing sql is:
CREATE EDITIONABLE TYPE "ORCL"."OID_TAB1" OID 'FB3CF41KK327B011D053F114ABBC878C' AS OBJECT (
className1 VARCHAR2(200),
id1 NUMBER)


Run below query in the database and check for TPYE_ODI exists or not
 
SQL> select OWNER, TYPE_NAME from DBA_TYPES where TYPE_OID='FB3CF41KK327B011D053F114ABBC878C ';

OWNER TYPE_OID
------------------------------------------ --------------------------------
ORCL      FB3CF41KK327B011D053F114ABBC878C

In most cases you will see the ODI is already exists in the database. The ODI already exists, and you cannot create ODI with same name that’s why it failed. You need to follow one of the options.

1. Create the object with new ODI – You can remove the ODI clause from the statement and run again. The database will generate new ODI for the object.

2. Drop the existing TYPE_ODI and reimport - DROP the object and reimport so that object will create with same ODI

3. In “impdp” use the parameter transform=oid:n - Using the parameter during the impdp will import TYPES with new ODI.

I have used all 3 methods based upon different scenarios.

Thanks & Regards,
http://oracleracexpert.com




Monday, October 16, 2023

WARNING: inbound connection timed out (ORA-3136)

The ORA-3136 will be written into alert.log when users fails to provide credentials and cannot authenticate within the set timeout value.

The default value set for below parameters in sqlnet.ora is 60 seconds.

SQLNET.INBOUND_CONNECT_TIMEOUT
INBOUND_CONNECT_TIMEOUT_listener_name

You will see below error in the alert.log file

Fatal NI connect error 12170.
VERSION INFORMATION:
TNS for Linux: Version 19.0.0.0.0 - Production
Oracle Bequeath NT Protocol Adapter for Linux: Version 19.0.0.0.0 - Production
TCP/IP NT Protocol Adapter for Linux: Version 19.0.0.0.0 - Production
Version 19.5.0.0.0
Time: 14-OCT-2023 18:06:02
Tracing not turned on.
Tns error struct:
ns main err code: 12535

TNS-12535: TNS:operation timed out
ns secondary err code: 12606
nt main err code: 0
nt secondary err code: 0
nt OS err code: 0
Client address: (ADDRESS=(PROTOCOL=tcp)(HOST=xxx.xx.xxx.xx)(PORT=51290))
2023-10-12T16:06:02.222415-07:00
WARNING: inbound connection timed out (ORA-3136)
2023-10-12T16:15:18.866821-07:00


In the above log you can see the client IP and port, you can able to check corresponding entry in the listener log as well. Also, you can see the time stamp of user initiated the connection and time stamp when user got error, it will be more than 60 sec.

The main reason for the error is …

1. When user or application trying to connect using wrong credentials or no attend made under 1 min threshold default value of the instance.

You can able to reproduce the issue by entering wrong credentials
 
SQL> sqlplus HR/xxxx@orcl
SQL*Plus: Release 19.0.0.0.0 - Production on Fri Oct 13 19:31:30 2023
Version 19.18.0.0.0
Copyright (c) 1982, 2022, Oracle. All rights reserved.

ERROR:
ORA-01017: invalid username/password; logon denied

$ tail -f orcl_alert.log
Fri Oct 13 19:32:31 2023
WARNING: inbound connection timed out (ORA-3136)

2. If the database has some performance issues or any network delay can cause long time and cannot authenticate user within default time out i.e. 60 seconds

If the database has some load causing the slowness, then increasing SQLNET.INBOUND_CONNECT_TIMEOUT to higher value will help to reduce the errors.

No DB restart required when you make the change in sqlnet.ora but note that it will be applicable to next server process.

3. The server receives the request but cannot be able to authenticate with in default time out i.e. 60 seconds

Find out what causing the delay in authentication if required increase the time out value.

If you are receiving error frequently you can enable tracing using below command
SQL> alter system set events '3136 trace name errorstack level 3';
 
You can trun off tracing using
SQL> alter system set events '3136 trace name context off';

Note that tracing will be generated under USER_DUMP_DEST or BACKGROUND_DUMP_DEST

If you still seeing these warnings I would suggest to raise a ticket with oracle support

Thanks,
https://oracleracexpert.com

Monday, August 14, 2023

Article: Mastering Data History using Oracle's Flashback Data Archive Feature

The Historical data is key for business decisions and having reliable data is very important for organizations. There are frequent implications for both financial and legal data for organizations and having a secure and accurate history of change of data is crucial for business.

Oracle Flashback technology offers significant benefits for database management and recovery. 

Please see the below article how it will help to meet the organizational needs.



Thanks,
https://oracleracexpert.com

Thursday, August 10, 2023

SELECT without FROM Clause in Oracle 23c

Oracle 23c has many new features and “SELECT without FROM” is one of the features. By using this feature, you can run queries without using FROM clause and specifying table name for testing expressions to get the results which can be easy of use for developers.

You will no longer receive error “ORA-00923: FROM keyword not found where expected” when running expressions to get results in Oracle 23c. 

Here are few examples

Example 1: Run mathematical operations with or without using FROM clause and you will get the result

SQL> select 2+3 from dual;
SQL> select 2+3 ;

Example 2: Select current date with and without using FROM clause and you will get the result.

SQL> Select current_date from dual;
SQL> Select current_date;

Example 3: Select NEXTVAL with and without using FROM clause and you will get the result

SQL> Create sequence empno_seq;
 
SQL> select empno_seq.nextval from dual;
SQL> select empno_seq.nextval ;

Example 4: Pl/SQL block with and without using FROM clause and you will get the result
delcare
v1 number;
begin
select empno_seq.nextval into v1 from dual;
dbms_output.put_line ('v1= '||v1);
end;
/

delcare
v1 number;
begin
select empno_seq.nextval into v1;
dbms_output.put_line ('v1= '||v1);
end;
/

Many other databases such as MS SQL Server, MYSQL support without FROM clause, this will help improve SQL Code portability.

Thanks

Friday, July 21, 2023

Flashback Data Archive enhancements in Oracle 12c

Flashback feature uses Automatic Undo Management for historical and metadata transactions. Flashback Data archive (FDA) feature introduced in Oracle 11g for undo-based flashback operations, and it is configured using retention time. Flashback data archive supported for multitenant (12.1.0.2 and above versions) as well using local or shared undo configuration.

Oracle 12c (12.1.0.1) has below enhancements in FDA

  • Data Hardening
  • User context tracking
Data Hardening This feature helps to associate set of tables for a specific application, so that you can enable Flashback Data archive for all those tables in a single command. Use DMBS_FLASHBACK_ARCHIVE.REGISTER_APPLICATION to register an application

You can create new application using REGISTER_APPLICATION

SQL> Begin
DBMS_FLASHBACK_ARCHIVE.register_application(
application_name => 'ORACLERACEXPERT',
flashback_archive_name => 'FDA1');
end;
/


You can add tables to the application using ADD_TABLE_TO_APPLICATION procedure

SQL> Begin
DBMS_FLASHBACK_ARCHIVE.ADD_TABLE_TO_APPLICATION (
application_name=> 'ORACLERACEXPERT', 
table_name=> 'EMP' , 
schema_name -> 'USER1');
end;
/


SQL> Begin
DBMS_FLASHBACK_ARCHIVE.ADD_TABLE_TO_APPLICATION (
application_name=> 'ORACLERACEXPERT', 
table_name=> 'DEPT' , 
schema_name -> 'USER1');
end;
/


You can remove the tables using REMOVE_TABLE_FROM_APPLICATION procedure from

The application will not enable automatically, use ENABLE_APPLICATION procedure to enable Flashback Data Archive for all tables in the specified application.

SQL> Begin
DBMS_FLASHBACK_ARCHIVE.enable_application(
application_name => 'ORACLERACEXPERT');
end;
/


To disable the application use disable_application procedure

SQL> Begin
DBMS_FLASHBACK_ARCHIVE.disable_application(
application_name => 'ORACLERACEXPERT');
end;
/


User context tracking - By enabling this feature it is easy to track which user made what changes to the table.

Use DMBS_FLASHBACK_ARCHIVE.SET_CONTEXT_LEVEL procedure to Set the user content level and procedure DMBS_FLASHBACK_ARCHIVE.GET_SYS_CONTEXT procedure To Access the context

There are 3 options depending upon how much user context needs to save
ALL – The entire SYS_CONTEXT is stored
TYPICAL – The user context is stored
NONE- Nothing

For ex: - To set context level to ALL
SQL> DBMS_FLASHBACK_ARCHIVE.SET_CONTEXT_LEVEL ( level=>‘ALL’);

You can get the XID from the archive table

SQL> select XID from SYS_FBA_HIST_93222;
XID
----------------
05000A0B7040000


Now with XID you can get the context information using dbms_flashback_archive.get_sys_context procedure


SQL> begin
dbms_output.put_line(dbms_flashback_archive.get_sys_context ('05000A0B7040000', 'USERENV', 'SESSION_USER'));
dbms_output.put_line(dbms_flashback_archive.get_sys_context ('05000A0B7040000', 'USERENV', 'HOST'));
dbms_output.put_line(dbms_flashback_archive.get_sys_context ('05000A0B7040000', 'USERENV', 'MODULE'));
end;

/
USER1
SRVHOST
SQL*Plus

You can get all Transactions ID using below query

SQL> select empno, empname, VERSIONS_XID
from EMP order by empno;

EMPNO EMPNAME VERSIONS_XID
----------- --------------- ---------------------
1              ORARAC    05000A0B7040000


You can use SYS_FBA_CONTEXT_AUD to get context information for each transaction.

There are many Flashback data archive view available and to get the list of all views run below query

SQL> SET PAGESIZE 1000
SQL> SET LINESIZE 600
SQL> COLUMN owner FORMAT A10
SQL> COLUMN table_name FORMAT A25

SQL> SELECT owner, table_name FROM dba_tables WHERE table_name LIKE '%FBA%';
 
OWNER       TABLE_NAME
--------------  -------------------------
SYS              SYS_FBA_FA
SYS              SYS_FBA_TSFA
SYS              SYS_FBA_TRACKEDTABLES
SYS              SYS_FBA_PARTITIONS
SYS              SYS_FBA_USERS
SYS              SYS_FBA_BARRIERSCN
SYS              SYS_FBA_DL
SYS              SYS_FBA_CONTEXT
SYS              SYS_FBA_CONTEXT_AUD
SYS              SYS_FBA_CONTEXT_LIST
SYS              SYS_FBA_APP
SYS              SYS_FBA_APP_TABLES
SYS              SYS_FBA_COLS
SYS              SYS_FBA_PERIOD
SYS              SYS_MFBA_STAGE_RID
SYS              SYS_MFBA_TRACKED_TXN
SYS              SYS_MFBA_NROW
SYS              SYS_MFBA_NCHANGE
SYS              SYS_MFBA_NTCRV


You can refer below Oracle Doc for best practices

FDA - Flashback Data Archive Usage and Best Practices (Doc ID 2370465.1)

Flashback Data Archive provides many benefits for maintaining historic data against tracked tables. The FDA helps to perform undo-based flashback operations for an extended period and take advantage of this feature.

Monday, June 19, 2023

Webinar: Oracle Database 23c Security new features

This Webinar helps you to understand Oracle Database 23c Security new features and head start using these features

Date and time: July 3rd 2023, 8:00am-9:00am
Pacific Daylight Time (San Francisco, GMT-07:00)

This Webinar covers following Topics.
  •  SQL Firewall
  •  Audit
  •  Authentication
  •  Authorization
  •  Encryption
  •  Autonomous Database
  •  Other
To register for this Webinar, please send an email to SatishbabuGunukula@gmail.com
You will receive an email confirmation with meeting link or Webinar link will be posted here.

Note that registrations are limited and first come and first serve basis.

For presentation link Click here

Thanks & Regards,
http://www.oracleracexpert.com

Thursday, June 8, 2023

Oracle 19c import issues ORA-31693, ORA-02354, ORA-39002, ORA-39405

When performing import come across the following issue

ORA-31693: Table data object "ORCL"."ITEMCG" failed to load/unload and is being skipped due to error:
ORA-02354: error in exporting/importing data
ORA-39840: A data load operation has detected data stream format error .
ORA-39844: Bad stream format detected: [klaprs_62] [139751105749101] [139751105749012] [4] [2] [2065583] [] []

User may encounter this issue when new column added to a table with cokumn optimization enabled and the same column was modified.

Below are the workarounds

  • Use access_method=EXTERNAL_TABLE during export
  • Prior export add and drop a dummy column to the problematic table using
SQL> ALTER TABLE <table_name> ADD dummy number;
SQL> ALTER TABLE <table_name> DROP dummy number;
  • Take export of failed table and import using CONTENT=DATA_ONLY as tableau structure already imported.

The fix for this bug was initially available on 19.13 and above see if it helps.

Also, I come across below issues when importing data

ORA-39002: invalid operation
ORA-39405: Oracle Data Pump does not support importing from a source database with TSTZ version 33 into a target database with TSTZ version 32.

User may encounter this issue when export from higher time zone version and importing into lower time zone version.
  • Patch the target database to higher or equal to source time zone patch or DST TZ version
  • Create a database with same time zone and perform export/import
For latest DST patches refer,
  • Oracle RDBMS and OJVM DST-related notes
  • Updated DST Transitions and New Time Zones in Oracle RDBMS and OJVM Time Zone File Patches (Doc ID 412160.1)

Hope this helps,

Thanks & Regards

Active Sessions, Proxy Sessions and Locked objects in Oracle

I have received few requests from Oracle User community to provide SQL queries related to active sessions, proxy sessions and locked objects in a session. Here are few SQL queries which you can use in day to day monitoring.
 
--------------------------------------------------------
--Script : ACTIVE SESSIONS
--Author : oracleracexpert.com
--------------------------------------------------------
SET PAGESIZE 1000
SET LINESIZE 600

COLUMN username FORMAT A10
COLUMN osuser FORMAT A10
COLUMN sid FORMAT 9999
COLUMN serial# FORMAT 999999999
COLUMN status FORMAT A10
COLUMN machine FORMAT A20
COLUMN program FORMAT A40
COLUMN module FORMAT A35
COLUMN action FORMAT A15
COLUMN logon_time FORMAT A20

SELECT s.username,
s.osuser,
s.sid,
s.serial#,
p.spid,
s.lockwait,
s.status,
s.machine,
s.program,
s.module,
s.action,
TO_CHAR(s.logon_Time,'MM-DD-YYYY HH24:MI:SS') AS logon_time,
s.blocking_session_status AS BlockStatus
FROM v$session s, v$process p
WHERE s.paddr = p.addr
AND s.status = 'ACTIVE'
ORDER BY s.username, s.osuser;

------------------------------------
--Script : Active Session waits
--Author : oracleracexpert.com
------------------------------------
SET PAGESIZE 1000
SET LINESIZE 600

COLUMN username FORMAT A10
COLUMN osuser FORMAT A10
COLUMN sid FORMAT 9999
COLUMN serial# FORMAT 999999999
COLUMN spid FORMAT A10
COLUMN state FORMAT A10
COLUMN wait_class FORMAT A20
COLUMN seconds_in_wait FORMAT 999999999
COLUMN module FORMAT A35
COLUMN blocking_session FORMAT A20
COLUMN blocking_session_status FORMAT A20

SELECT s.username,
       s.osuser,
       s.sid,
       s.serial#,
   p.spid, 
       s.state,
   s.wait_class,
       s.seconds_in_wait,
       s.module,
       TO_CHAR(s.logon_Time,'MM-DD-YYYY HH24:MI:SS') AS logon_time,
   s.blocking_session,
       s.blocking_session_status AS BlockStatus
FROM   v$session s, v$process p
WHERE  s.paddr  = p.addr
AND    s.status = 'ACTIVE'
ORDER BY 1,2;


--------------------------------------------------------
--Script : PROXY SESSIONS
--Author : oracleracexpert.com
--------------------------------------------------------

SET PAGESIZE 1000
SET LINESIZE 600

COLUMN username FORMAT A10
COLUMN osuser FORMAT A10
COLUMN sid FORMAT 9999
COLUMN serial# FORMAT 999999999
COLUMN status FORMAT A10
COLUMN machine FORMAT A20
COLUMN program FORMAT A40
COLUMN module FORMAT A35
COLUMN action FORMAT A15
COLUMN logon_time FORMAT A20

SELECT s.username,
s.osuser,
s.sid,
s.serial#,
p.spid,
s.lockwait,
s.status,
s.machine,
s.program,
s.module,
s.action,
TO_CHAR(s.logon_Time,'MM-DD-YYYY HH24:MI:SS') AS logon_time,
s.blocking_session_status AS BlockStatus
FROM  v$session s, v$process p, v$session_connect_info sci
WHERE s.paddr = p.addr
AND s.sid = sci.sid
AND s.serial# = sci.serial#
AND sci.authentication_type = 'PROXY'
ORDER BY s.username, s.osuser;

--------------------------------------------------------
--Script : LOCKED OBJECT SESSIONS
--Author : oracleracexpert.com
--------------------------------------------------------

SET PAGESIZE 1000
SET LINESIZE 600

COLUMN sid FORMAT 9999
COLUMN serial# FORMAT 999999999
COLUMN status FORMAT A10
COLUMN owner FORMAT A20
COLUMN object_owner FORMAT A20
COLUMN object_name FORMAT A30
COLUMN object_type FORMAT A15
COLUMN oracle_username FORMAT A15
COLUMN locked_mode FORMAT A15
COLUMN os_user_name FORMAT A15

SELECT s.sid,
s.serial#,
s.status,
do.owner,
do.object_name,
do.object_type,
lo.oracle_username,
Decode(lo.locked_mode, 0, 'None',
1, 'Null (NULL)',
2, 'Row-S (SS)',
3, 'Row-X (SX)',
4, 'Share (S)',
5, 'S/Row-X (SSX)',
6, 'Exclusive (X)',
lo.locked_mode) locked_mode,
lo.os_user_name
FROM v$locked_object lo, dba_objects do, v$session s
WHERE lo.session_id = s.sid
AND do.object_id = lo.object_id
ORDER BY 1, 2, 3, 4;

Thanks & Regards,
https://oracleracexpert.com

Tuesday, May 30, 2023

Errors ORA-12154, ORA-29003 when connecting to Autonomous Data Warehouse using Django

When connection to Autonomous Data Warehouse Using Django web framework first we come across “ORA-12154” error. That means Django cannot be able to connect to the Oracle Database service name with the settings in settings.py file.

File "C:\django\db\backends\oracle\base.py", line 254, in get_new_connection return Database.connect( cx_Oracle.DatabaseError: ORA-12154: TNS:could not resolve the connect identifier specified

First copy the tnsnames.ora into local system and test tnsping.

C:\> tnsping <service Name>

If the tnsping is working fine, then below are the passible reason for ORA-12154 error
  • TNS_ADMIN might not be configured or set the right path
  • There might be a typo in service name
  • Connection details in settings.py might not be correct
We found that TNS_ADMIN is not set to the right path and updating the correct path resolved the issue. But we have received new error

ORA-29003: SSL transport detected mismatched server certificate

Django supports Oracle Database 19c or higher versions but cx_oracle python driver required. We verified that required driver is installed. We try to connect using SQL*PLUS but still receiving same error. That means there is no issue with the settings.

After research we found that 12c client is not supported for new mTLS authentication as per document “ALERT: Action Required for Autonomous Databases (Doc ID 2911553.1)”

We have installed Oracle 19c client and were able to connect without any issues.

Below are the options to resolve the issue

1. Install certified oracle client versions 11.2.0.4.220719 (or later), 18.19 (or later), 19.2 (or later), 21 (base release or later)

2. Update Autonomous database instance to allow both TLS and mTLS authentication.
  • Goto Autonomous Database Details page --> Network --> click Edit in the Mutual TLS (mTLS) Authentication field.
  • Change the value to allow TLS authentication, deselect Require mutual TLS (mTLS) authentication
  • Click Update
3. Use ssl_server_dn_match=no in the connect string (when using 12c client updating the value to “no” didn’t help )

I hope this helps.

Thanks
Satishbabu G, Oracle ACE Pro

Oracle "Hyperion EPMA Server" service is not coming online

I have come across below issue wtih Oracle Hyperion. When we restarted Hyperion server, the “Hyperion EPMA Server” service is not coming online and application is down.

Here are the Errors from event.log

EPMA_Server

[EPMA Server Startup] ERROR SVR_ERR_PROCESSMGR_CANT_INIT_SESSIONMGR:Cannot initialize the Session Manager.Hyperion.DimensionServer.Interface.Exceptions.EPMAServiceException: Cannot initialize the Session Manager. ---> Hyperion.CommonServices.Exceptions.SessionManagerException: An error was encountered by the CAS Security Provider: Class: java.lang.NullPointerException

StackTrace:

at Hyperion.DimensionServer.SessionManager.CasSecurityProvider.GetDataBaseDetails(String& vendor, String& serverName, Int32& dbPort, String& dbName, String& username, String& password, String& jdbcUrl)

at Hyperion.DimensionServer.SessionManager.SessionManager.InitializeSqlConnectionString()

at Hyperion.DimensionServer.SessionManager.SessionManager.Initialize(String configFileName, Boolean restorePastInstanceSessions, Boolean enableCaching)

--- End of inner exception stack trace ---


Hyperion EPMA DimmensionServer

Service cannot be started. Hyperion.DimensionServer.Interface.Exceptions.EPMAServiceException: Cannot initialize the Session Manager. ---> Hyperion.CommonServices.Exceptions.SessionManagerException: An error was encountered by the CAS Security Provider: Class: java.lang.NullPointerException
StackTrace:
at Hyperion.DimensionServer.SessionManager.CasSecurityProvider.GetDataBaseDetails(String& vendor, String& serverName, Int32& dbPort, String& dbName, String& username, String& password, String& jdbcUrl)
at Hyperion.DimensionServer.SessionManager.SessionManager.InitializeSqlConnectionString()
at Hyperion.DimensionServer.SessionManager.SessionManager.Initialize(String configFileName, Boolean restorePastInstanceSessions, Boolean enableCaching)
--- End of inner exception stack trace ---


The event log is no much helpful. But note that the Hyperion EPMA Service will not come up if you have any issues with database. Check the logs to see any “ORA- “errors .

I found below error in EssbaseAdminServices0.log

#### <[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'> <> <> <> <1329242417925> ORA-28001: the password has expired

Now it’s clear that Database user password expired.

SQL> select USERNAME, ACCOUNT_STATUS from dba_users where USERNAME = ‘SHARED_SERVICES’;
USERNAME ACCOUNT_STATUS
------------------------------ --------------------------------
SHARED_SERVICES EXPIRED(GRACE)

Do not change the password. If you change the password then you need to re-configure the Hyperion service in order to use the new password.

If you know the password then set the using below command.
SQL> Alter user SHARED_SERVICES identified by ‘xxxxxx’;

If you don’t know the password then reset the password following below steps
SQL> select password from sys.user$ where name='SHARED_SERVICES';

PASSWORD
------------------------------
61266722B44D5BG418

SQL> alter user QWERTY identified by values '61266722B44D5BG418’;
User altered.

Also make sure to modify PASSWORD_LIFE_TIME to “UNLIMITED” for DEFAULT or User profile that you are using

SQL> alter profile default limit PASSWORD_LIFE_TIME unlimited;
Profile altered.

Regards,
Satishbabu Gunukula
http://www.oracleracexpert.com

Sunday, May 14, 2023

UN World Innovation Day: Igniting Change through Creativity and Collaboration

Whenever there is a global challenge, the Innovation has always played an important role to solving challenges. Every year the United Nations celebrates Innovation Day on the 21st of April to recognizes the importance of innovation in harnessing the economic potential of nations. As world faces unprecedented crises in health, education, the future of work and economy, it is important for us to find innovative solutions together

The United Nations (UN) has set forth 17 Sustainable Development Goals (SDGs) to tackle wide range of global challenges by 2030 which includes climate change, poverty, eradication and beyond. We will explore how Generative Artificial Intelligence (AI) can be used to achieve of these goals for better future.

                           

The UN World Innovation Day Hack 2023 is not just another hackathon; it's a unique opportunity to collaborate with encouraging individuals to creatively utilize their skills to generate new ideas and solutions for various critical areas. These include health and wellbeing, economic growth, decent work, and quality education. Hackathon brings together creative minds from around the world to generate innovative solutions for pressing issues. By bringing together a diverse group of talented individuals, the hackathon helps to provide meaningful solutions to pressing challenges.

Hackathon gives an opportunity to connect with new people from various backgrounds, experiences and expertise come together to collaborate, share ideas, and push the boundaries of innovation. You will have the opportunity to learn from each other, explore, generate innovative solutions, and network with inspiring individual beyond the event.

This year's hackathon introduces two brand new challenges:
  • GPT4Good
  • Data4Good
These challenges can address crucial areas where innovation can make a significant impact.

In the "GPT4Good" challenge, participants will explore the potential of GPT (Generative Pre-trained Transformer) models to address social, environmental, and humanitarian issues. The GPT is a cutting-edge artificial intelligence technology, has the power to generate human-like text, making it a valuable tool for various applications. From enhancing accessibility to fostering sustainable practices, participants will harness the power of GPT to create innovative solutions that contribute to the greater good.



The "Data4Good" challenge focuses on leveraging the power of data to drive positive change. With the proliferation of data in our digital age, there is a tremendous opportunity to extract insights and make informed decisions that benefit society. To address critical issues such as participants will work with diverse datasets, apply data analytics, visualization, and machine learning techniques to address critical issues. Participants will be encouraged to explore how data can be ethically collected, analyzed, and utilized to address pressing global issues.

The UN World Innovation Day Hack 2023 event schedule, spanning from May12th to May 15th, promises an exhilarating journey filled with creativity, collaboration, and problem-solving.



The UN World Innovation Day Hack 2023 is made possible through collaboration with Hackmakers, a global community of changemakers and innovators, joins hands with sponsors such as Oracle, AI4Diversity, Polygon, Unstoppable Domains, Buzzy and Wand to support this event. These organizations bring their expertise, resources, and mentorship to provide participants with the necessary tools to transform their ideas into tangible solutions.

The Hackathons bring over 1000+ participants and mentors around the world. In this blog post, I express my deep gratitude to all the mentors who generously contribute their time, expertise, and support to guide teams and projects during these hackathons as they play essential role in making these events successful.

To find answers to common queries and gain a better understanding of the hackathon logistics visit the official hackathon FAQ page at https://www.worldinnovationday.com/faq .

To access valuable resources and guides visit resources page at https://www.worldinnovationday.com/resources. It will provide necessary tools and knowledge to overcome challenges and push the boundaries of innovation.

To access Challenge and Sponsored resources details, visit the challenge resource page
https://www.worldinnovationday.com/challenge-resources.

Join on this transformative journey, meet incredible individuals, test your skills, and deliver meaningful impacts. Together, let's unleash the potential of innovation and create a world that thrives on collaboration, inclusivity, and positive change.

Conclusion: The UN World Innovation Day Hack 2023 is a global celebration of creativity, collaboration, and innovation. As an official Mentor for this event, I am honored to be part of a community to address pressing global challenges through technology and creative thinking. As we work together, let us continue to inspire, guide, and empower the next generation of innovators for better future.


#WorldInnovationDay #Hackathon #GptForGood #DataForGood #Innovation #Collaboration

Regards
Satishbabu G, Oracle ACE Pro


Thursday, March 2, 2023

Oracle AutoUpgrade with source and Target Database on different servers

AutoUpgrade utility can be used on upgrading databases from 12c R2 release (12.2 + DBJAN2019RU and newer) and it has Analyze, Fixup, Deploy and Upgrade processing modes. 

Before you proceed make sure you meet following requirements.
  • create config file
  • Source Database should be running in original oracle home
  • The Database server should be registered in DNS
  • JAVA8 required for Autoupgrade to run. Oracle 12c R2 (12.2.0.1) or newer oracle homes have a java version by default.
  • If you run AutoUpgrade in batch or script mode use “noconsole” parameter
From Oracle 19c (10.3) autoupgrade.jar file exists by default, for earlier releases you must download latest autoupgrade.jar file from Oracle support.

There are four AutoUpgrade modes and each mode performs different steps
  •  Analyze Mode: Setup, Pre-checks.
  • Fixups Mode: Setup, Pre-checks, and Pre-fixups.
  • Deploy Mode: Setup, Guaranteed Restore Point, Pre-upgrade, Pre-checks, Pre-fixups, Drain,      Database Upgrade, Post-checks, Post-fixups, and Post-upgrade.
  • Upgrade Mode: Setup, Database Upgrade, Post-checks, and Post-fixups.
Analyze Mode: This mode runs few checks to see weather database is ready for upgrade. In this mode it only reads data from database to analyze and does not perform any changes.

You can run this step on source database before you setup target.

Run below command to start AutoUpgrade Analyze

$ORACLE_HOME/jdk/bin/java -jar $ORACLE_HOME/rdbms/admin/autoupgrade.jar – config /home/oracle/autoupgrade/config.txt -mode analyze

Make sure you analyze output files for errors and run fixup on Source database server. You should see SID.html and SID_preupgrade.log files

Note that this mode also generates status files such as status.json, progress.json which can be located under cfgtoollogs/upgrade/auto/status.

Status.json – This file contains High level status of upgrade.
Progress.json – This file has contains status of progress of all upgrades

In case if target database is not on the same server then you must set the source home path in the configuration file, so that Autoupgrade analyze can run on source oracle home.

For example,
upgrade1.source_home=/home/oracle/product/12.2.0.1/dbhome_1 # Source ORACLE_HOME Path
upgrade1.target_home=/home/oracle/product/19.0.0.0/dbhome_1 # Target ORACLE_HOME Path

Fixups Mode : This mode performs all required automated fix up that are required before you start an upgrade. In this mode it creates guaranteed restore point.

Run below command on source Database server to run fixups.

$ORACLE_HOME/jdk/bin/java -jar $ORACLE_HOME/rdbms/admin/autoupgrade.jar – config /home/oracle/autoupgrade/config.txt -mode fixups

Deploy Mode: This mode performs all required actions for an upgrade, which include analyze, fixups, upgrade and post upgrade steps. You will use this mode when source and target Oracle Home’s are on the same server. This mode also creates guaranteed restore point.

Run below command on source Database server to run fixups.

$ORACLE_HOME/jdk/bin/java -jar $ORACLE_HOME/rdbms/admin/autoupgrade.jar – config /home/oracle/autoupgrade/config.txt -mode Deploy

Move the database from source to Target Database server and perform Upgrade mode.

Upgrade Mode: You will run this Autoupgrade mode when you are moving database to Target server or don’t have source Oracle home access. This mode is used only when you are moving to new server. But note that this mode doesn’t create guaranteed restore point and it doesn’t perform the post upgrade steps.

Before you perform upgrade make sure you copy the during_upgrade_pfile_dbname.ora from source to target Oracle Home with default name init<SID>.ora. You can also create the spfile using during_upgrade_pfile_dbname.ora which can be found under temp directory.

SQL> create spfile from pfile=' /home/oracle/autoupgrade/au21/TESTDB/temp/during_upgrade_pfile_testdb.ora';

On Target database server start the database in upgrade mode and run below command to upgrade

$ORACLE_HOME/jdk/bin/java -jar $ORACLE_HOME/rdbms/admin/autoupgrade.jar – config /home/oracle/autoupgrade/config.txt -mode upgrade

After upgrade make sure you perform post upgrade steps manually

· Copy network files sql.net ora, listener,ora, tnsnames.ora files..etc
· Restart of database in case of RAC
· Remove guaranteed restore point

Thanks & Regards,
https://oracleracexpert.com, Oracle ACE

Wednesday, February 22, 2023

Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class

When launching Database configuration assistant (DBCA) you may encounter this error. The “java.lang.NoClassDefFoundError” error encounter when it could not initialize class “sun.awt.X11.XToolkit”. 

This normally occur when launching Graphic user interface (GUI)

No protocol specified
Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11.XToolkit
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at java.awt.Toolkit$2.run(Toolkit.java:860)
at java.awt.Toolkit$2.run(Toolkit.java:855)
at java.security.AccessController.doPrivileged(Native Method)
at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:854)
at com.jgoodies.looks.LookUtils.isLowResolution(LookUtils.java:484)
at com.jgoodies.looks.LookUtils.<clinit>(LookUtils.java:249)
at com.jgoodies.looks.plastic.PlasticLookAndFeel.<clinit>(PlasticLookAndFeel.java:135)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at javax.swing.SwingUtilities.loadSystemClass(SwingUtilities.java:1879)
at javax.swing.UIManager.setLookAndFeel(UIManager.java:582)
at oracle.install.commons.util.Application.startup(Application.java:976)
at oracle.install.commons.flow.FlowApplication.startup(FlowApplication.java:181)
at oracle.install.commons.flow.FlowApplication.startup(FlowApplication.java:198)
at oracle.assistants.common.base.driver.AssistantApplication.startup(AssistantApplication.java:336)
at oracle.assistants.dbca.driver.DBConfigurator.startup(DBConfigurator.java:378)
at oracle.assistants.dbca.driver.DBConfigurator.main(DBConfigurator.java:513)

The main causes of the issue is
1. The DISPLAY variable is NOT set or value is not correct.
2. X Windows is not installed
3. Oracle user not added to ACL (Access Control List)

If launching from server make sure you have any X Windows software installed and install org-x11-apps.x86_64 package

If you are launching from a local workstation, make sure you have XGraphics software such as Exceed, VLC…etc tools installed. Then You can set DISPLAY by using below command

CSH
$ setenv DISPLAY <IP Address of workstation or server>:0

SSH or KSH
$ export DISPLAY=<IP Address of workstation or server>:0

In Some cases, users may face issue when installing Oracle software on Ubuntu or Linux environment.

>>> Could not execute auto check for display colors using command /usr/bin/xdpyinfo. Check if the DISPLAY variable is set. Failed <<<<

Some requirement checks failed. You must fulfill these requirements before
continuing with the installation,
Continue? (y/n) [n] Y

>>> Ignoring required pre-requisite failures. Continuing...
Preparing to launch Oracle Universal Installer from /tmp/OraInstall2019-08-01_12-17-01PM. Please wait ....oracle$:~$ No protocol specified
Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11.XToolkit

In this scenario, verify weather JDK installed on the system or not using below command
$ java -version

If not installed then installing required JDK will resolve the issue. If the problem persists, then run below command by logging as root

$ xhost +

Switch back to Oracle user and run the installation.

Thanks,
https://oracleracexpert.com, Oracle ACE Pro

Thursday, February 16, 2023

Upgrade Oracle Database using AutoUpgrade Utility

Autoupgrade is used to upgrade one or more databases using command line. Using the tool, you can run pre-upgrade tasks that will provide the fixups, all recommended fixups must be executed before upgrading the database and finish the upgrade by running the post-upgrade tasks. By using this utility you can upgrade hundreds of databases with one command.

It is always recommending that you run AutoUpgrade in Analyze mode before running in Fixup mode. Note that fixup mode can make changes to the source database. The Autoupgrade includes automatic retry and fallback, schedule upgrades and modify or remove the initialization parameters which are deprecated.

AutoUpgrade utility can be used on upgrading databases from 12c R2 release (12.2 + DBJAN2019RU and newer)

You need to download AutoUpgrade utility for Databases 12c R2 and 18c. From 19.3 (19c) and later the autoupgrade.jar file exists by default.

Oracle home must contain JAVA to use AutoUpgrade Tool. Always download latest AutoUpgrade.jar file

Create a sample config.txt file for database ugrade

upgrade1.sid=TESTDB                       # ORACLE_SID of source DB
upgrade1.run_utlrp=no                       # Optional. To run utlrp after upgrade select YES
upgrade1.timezone_upg=no                # Optional. To run the timezone upgrade select YES
upgrade1.start_time=now                    # Optional Use “NOW” or specify future upgrade time and date [+XhYm (X hours, Y minutes) | dd/mm/yyyy hh:mm:ss]      
upgrade1.upgrade_node=localhost    # Optional. Default is 'localhost'
upgrade1.target_version=19               # Only required if target database version is 12.2
upgrade1.log_dir= /home/oracle/cfgtoollogs/autoupgrade/TESTDB # Log dir path for the upgrade job
upgrade1.source_home=/home/oracle/product/12.2.0.1/dbhome_1  # Source ORACLE_HOME Path 
upgrade1.target_home=/home/oracle/product/19.0.0.0/dbhome_1   # Target ORACLE_HOME Path 

AutoUpgrade with source and Target Database on same server
  • Run below command to start AutoUpgrade Analyze
$ORACLE_HOME/jdk/bin/java -jar $ORACLE_HOME/rdbms/admin/autoupgrade.jar – config /home/oracle/autoupgrade/config.txt -mode analyze
AutoUpgrade utility launched with default options
Processing config file ...
+--------------------------------+
| Starting AutoUpgrade execution |
+--------------------------------+
1 databases will be analyzed
Type 'help' to list console commands
upg> Job 100 completed
------------------- Final Summary --------------------
Number of databases [ 1 ]
Jobs finished [1]
Jobs failed [0]
Jobs pending [0]
------------------- JOBS FINISHED SUCCESSFULLY --------------------
Job 100 for TESTDB

All the logs are under the job id . Pls review all the logs for any errors and information.

You can see the warnings and errors in html file.

 

  • Run below command to start deployment of upgrade on same server
$ORACLE_HOME/jdk/bin/java -jar $ORACLE_HOME/rdbms/admin/autoupgrade.jar – config /home/oracle/autoupgrade/config.txt -mode deploy

AutoUpgrade utility launched with default options
Processing config file ...
+--------------------------------+
| Starting AutoUpgrade execution |
+--------------------------------+
1 databases will be processed
Type 'help' to list console commands
upg>


upg> lsj
+----+-------+---------+---------+-------+--------------+--------+---------------+
|Job#|DB_NAME| STAGE|OPERATION| STATUS| START_TIME| UPDATED| MESSAGE|
+----+-------+---------+---------+-------+--------------+--------+---------------+
| 102| TESTDB|DBUPGRADE|EXECUTING|RUNNING|21/05/12 15:03|15:35:22|95% Upgraded |
+----+-------+---------+---------+-------+--------------+--------+---------------+
Total jobs 1

Once upgrade is completed verify upg_summary.log for any errors

/u01/home/oracle:DBA>cat upg_summary.log
Oracle Database Release 19 Post-Upgrade Status Utility 04-30-2021 11:07:0
Database Name: TESTDB
Component Current Full Elapsed Time
Name Status Version HH:MM:SS
Oracle Server UPGRADED 19.10.0.0.0 00:09:54
JServer JAVA Virtual Machine VALID 19.10.0.0.0 00:01:12
Oracle XDK UPGRADED 19.10.0.0.0 00:00:38
Oracle Database Java Packages UPGRADED 19.10.0.0.0 00:00:05
Oracle Text UPGRADED 19.10.0.0.0 00:00:23
Oracle Workspace Manager UPGRADED 19.10.0.0.0 00:00:22
Oracle Real Application Clusters OPTION OFF 19.10.0.0.0 00:00:00
Oracle XML Database UPGRADED 19.10.0.0.0 00:00:51
Oracle Multimedia UPGRADED 19.10.0.0.0 00:01:47
Datapatch 00:01:41
Final Actions 00:01:44
Post Upgrade 00:00:16

Total Upgrade Time: 00:17:31

Database time zone version is 26. It is older than current release time
          zone version 32. Time zone upgrade is needed using the DBMS_DST package.

          Grand Total Upgrade Time: [0d:0h:20m:20s]


If you select upgrade1.timezone_upg=YES then Time zone will be upgraded as part of the Database upgrade. 

AutoUpgrade Stages

AutoUpgrade utility go through series of steps called stages but the actions performed during every stage defined by the “processing mode”. For AutoUpgrade we have Analyze, Fixups, Deploy, and Upgrade processing modes.

AutoUpgrade has the following stages: 
  • SETUP: The initial stage in which it starts the job.
  • PREUPGRADE: The stage in which it performs readiness for upgrade such as sufficient space
  • PRECHECKS: The stage in which it performs pre-checks on source Oracle home to meet requirements for upgrade.
  • GRP: Backup database using guaranteed restore point (GRP) before upgrade, this option only available in Enterprise Edition only
  • PREFIXUPS: The stage in which it performs preupgrade fixups before upgrade
  • DRAIN: The stage during which it shuts down the database to release resources.
  • DBUPGRADE: The stage in which it performs the actual upgrade.
  • POSTCHECKS: The stage in which it performs post upgrade checks on the target Oracle home before executing any postupgrade fixups.
  • POSTFIXUPS: The stage in which it performs processing of postupgrade fixups, timezone upgrade is part of this step.
  • POSTUPGRADE: The stage in which in copies or merges the required files from to the target Oracle home for ex:- listener, tns files
There are 2 operational modes during Autoupgrade, i.e. PREPARING and EXECUTING

There are 4 state messages
  • RUNNING – AutoUpgrade is still running
  • FINISHED - AutoUpgrade is successfully completed
  • ERROR – AutoUpgrade has some Errors
  • ABORTED - AutoUpgrade aborted response to user request.
Refer useful oracle support notes
Thanks & Regards,
https://oracleracexpert.com, Oracle ACE

Create, Drop, Alter Blockchain tables in Oracle 21c

Blockchain tables are designed to allow insert operations only, updates and any modifications are not allowed, and delete operations are restricted. The rows are organized into chains by storing previous row’s hash values in the current row and chain of rows is verifiable by all participants. The blockchain tables concept introduced in Oracle 21c and can be backported to 19c using a patch 32431413, but COMPATIBLE parameter must be set to 19.10.0 or late

Create and Drop Blockchain table

When creating block chain you can specify retention period for Blockchain table using “NO DROP” Clause in the CREATE BLOCKCHAIN TABLE statement to specify retention period and to specify retention period for rows use “NO DELETE” Clause .

Ex:- In below example creates Blockchain_T1 table the table can be dropped until 10 days and rows can be deleted until 15 days that they were inserted.

SQL> CREATE BLOCKCHAIN TABLE Blockchain_T1 (Col1 NUMBER, Col2 VARCHAR2(48), Col3 DATE)
NO DROP UNTIL 10 DAYS IDLE
NO DELETE UNTIL 15 DAYS AFTER INSERT
HASHING USING "SHA2_512" VERSION "v1";


Table level clauses
  • NO DROP – The table cannot be dropped. 
  • NO DROP UNTIL x DAYS IDLE – Table cannot be dropped when the table is IDLE and no new rows created for specified X number of days or retention period
Where X is the number of days.

Row level clauses
  • NO DELETE or NO DELETE LOCKED – The Rows cannot be deleted.
  • NO DELETE UNTIL x DAYS AFTER INSERT – the rows cannot be deleted until x number of days they were inserted, the retention setting can be changed using ALTER TABLE command.
  • NO DELETE UNTIL x DAYS AFTER INSERT LOCKED – the rows cannot be deleted until x number of days they were inserted , also retention setting cannot be changed until x number of days
Create partition on Blockchain table

In below example creates Blockchain_T1 table with partitions. The table cannot be dropped until 10 days and rows cannot be deleted until 15 days that they were inserted.

SQL> CREATE BLOCKCHAIN TABLE Blockchain_T1 (Col1 NUMBER, Col2 VARCHAR2(48), Col3 DATE)
NO DROP UNTIL 10 DAYS IDLE
NO DELETE UNTIL 15 DAYS AFTER INSERT
HASHING USING "SHA2_512" VERSION "v1"
PARTITION BY RANGE(Col3)
(PARTITION p1 VALUES LESS THAN (TO_DATE('01-31-2022','mm-dd-yyyy')),
PARTITION p2 VALUES LESS THAN (TO_DATE('02-28-2022','mm-dd-yyyy')),
PARTITION p3 VALUES LESS THAN (TO_DATE('03-31-2022','mm-dd-yyyy'))
);


You can query USER_TAB_COLS for Blockchain Table details

SQL> SELECT internal_column_id as colid
column_name
data_type,
data_length,
FROM user_tab_cols
WHERE table_name = 'BLOCKCHAIN_T1'
ORDER BY colid;

COLID COLUMN_NAME DATA_TYPE DATA_LENGTH
---------- ------------------------ ------------------------------ -----------

1 Col1 NUMBER 22
2 Col2_ VARCHAR2(48) 48
3 Col3T DATE 7
4 ORABCTAB_INST_ID$ NUMBER 22
5 ORABCTAB_CHAIN_ID$ NUMBER 22
6 ORABCTAB_SEQ_NUM$ NUMBER 22
7 ORABCTAB_CREATION_TIME$ TIMESTAMP(6) WITH TIME ZONE 13
8 ORABCTAB_USER_NUMBER$ NUMBER 22
9 ORABCTAB_HASH$ RAW 2000
10 ORABCTAB_SIGNATURE$ RAW 2000
11 ORABCTAB_SIGNATURE_ALG$ NUMBER 22
12 ORABCTAB_SIGNATURE_CERT$ RAW 16
13 ORABCTAB_SPARE$ RAW 2000


13 rows selected.

You can query {CDB|DBA|ALL|USER}_BLOCKCHAIN_TABLES views to get information about Blockchain Tables

DROP - The below example drops the table if the table has not modified for retention period defined in the Blockchain creation.

SQL> DROP TABLE Blockchain_T1 PURGE;

It is recommended to use PURGE option when dropping a Blockchain table.
 
Note that Blockchain tables cannot be create the root container and application root container.

 In below example Blockchain_T2 table creation failed as it cannot be created in root container

SQL> CREATE BLOCKCHAIN TABLE Blockchain_T2 (Col4 NUMBER, Col2 VARCHAR2(48), Col3 DATE)
NO DROP UNTIL 10 DAYS IDLE
NO DELETE LOCKED
HASHING USING "SHA2_512" VERSION "v1";


Error report -
ORA-05729: blockchain table cannot be created in root container

ALTER Blockchain Tables : The Blockchain table retention can be modified using ALTER TABLE command

In below example we increased retention for Blockchain_T1 table that it cannot be dropped until table IDLE and no new rows created for 21 days.

SQL> ALTER TABLE Blockchain_T1 NO DROP UNTIL 21 DAYS IDLE;

In below example trying to lower retention for Blockchain_T1 table to 16 and the operation failed as retention value cannot be lowered.

SQL> ALTER TABLE Blockchain_T1 NO DROP UNTIL 16 DAYS IDLE;

Error report -
ORA-05732: retention value cannot be lowered

You can also increase column length but cannot add or drop column in Blockchain tables.
SQL> ALTER TABLE Blockchain_T1 MODIFY (COL2 VARCHAR2(58));

Table BLOCKCHAIN_T1 altered.

ADD column 
SQL> ALTER TABLE Blockchain_T1 ADD (Col4 varchar2(32));

Error report -
ORA-05715: operation not allowed on the blockchain table

DROP column 
SQL> ALTER TABLE Blockchain_T1 DROP column Col2;

Error report -
ORA-05715: operation not allowed on the blockchain table

DDL and DML on Block chain

In below example we are trying to DELETE, TRUNCATE, UPDATE and MOVE the operation not allowed

DELETE Table
SQL> DELETE FROM Blockchain_T1 where Col1 = 1;

Error report -
SQL Error: ORA-05715: operation not allowed on the blockchain table

TRUNCATE Table
SQL> TRUNCATE TABLE Blockchain_T1;

Error report -
ORA-05715: operation not allowed on the blockchain table

UPDATE Table
SQL> UPDATE Blockchain_T1 SET Col2=“Test” WHERE id = 1;

Error report -
SQL Error: ORA-05715: operation not allowed on the blockchain table

DROP TABLE
SQL> DROP TABLE Blockchain_T1;

Error report -
ORA-05723: drop blockchain table BLOCKCHAIN_T1 not allowed

MOVE Table
SQL> ALTER TABLE Blockchain_T1 move tablespace Blockchain_TBS2 ;

Error report -
ORA-05715: operation not allowed on the blockchain table

Pls refer  Restrictions for Blockchain tables for more details.

Thanks & Regards
https://oracleracexpert.com, Oracle ACE

Wednesday, February 15, 2023

BlockChain Tables in Oracle 21c

Blockchain tables are designed to allow insert operations only, updates and any modifications are not allowed, and delete operations are restricted. The rows are organized into chains by storing previous row’s hash values in the current row and chain of rows is verifiable by all participants.

Oracle 19c introduced Immutable tables concept, that provides protection against unauthorized data modifications. The blockchain tables concept introduced in Oracle 21c and can be backported to 19c using a patch 32431413, but COMPATIBLE parameter must be set to 19.10.0 or late.

These tables are useful to implement Blockchain applications to handle tamper-resistant blockchain transactions with verifiable crypto-secure data management practices. The blockchain tables prevent unauthorized changes or deletion by criminals, hackers and fraud and protect critical company data. Blockchain tables has hidden columns as well and these values are managed by the database.

Blockchain tables and regular tables can be used in queries and transactions, also you can create indexes and partitions.

Blockchain tables hidden columns

Column Name

Data Type

Description

ORABCTAB_INST_ID$

NUMBER (22)

Instance ID of the database instance into which the row is inserted.

ORABCTAB_CHAIN_ID$

NUMBER (22)

Chain ID of the chain, in the database instance, into which the row is inserted.  0 through 31 are valid values.

ORABCTAB_SEQ_NUM$

NUMBER(22)

Sequence number of the row on the chain

ORABCTAB_CREATION_TIME$

TIMESTAMP WITH TIME ZONE

Row created time in UTC format

ORABCTAB_USER_NUMBER$

NUMBER (22)

Database User ID who inserted the row.

ORABCTAB_HASH$

RAW(2000)

Hash value of the row

ORABCTAB_SIGNATURE$

RAW(2000)

User signature of the row

ORABCTAB_SIGNATURE_ALG$

NUMBER(22)

Signature algorithm used to produce the user signature of a signed row.

ORABCTAB_SIGNATURE_CERT$

RAW(16)

GUID of the certificate associated with the signature on a signed row.

ORABCTAB_SPARE$

RAW(2000)

Reserved for future use.


Important Guidelines for Blockchain Tables

  • In case of Oracle RAC instance, a block chain table contains 32 chains and chain will have unique combination of instance ID and chain ID. It is recommended to create index on the combination of Instance ID, chain ID and sequence number.
  • The SHA2-512 hashing algorithm used to handle hash value
  • In case Oracle Data Guard, to avoid data loss consider using Maximum availability or Maximum protection mode
  • To specify retention period for Blockchain table use “NO DROP” Clause in the CREATE BLOCKCHAIN TABLE statement to specify retention period.
  • To specify retention period for rows in Blockchain table use “NO DELETE” Clause in the CREATE BLOCKCHAIN TABLE statement to specify retention period for rows

Restrictions for Blockchain tables

  • There are many restrictions when using blockchain tables
  • Many datatypes are not supported such as nested table , varray, REF , ROWID, UROWID, LONG, object type, BFILE, XMLType , , , TIMESTAMP WITH TIME ZONE, TIMESTAMP WITH LOCAL TIME ZONE
  • Point-in-time recovery or flashback database will undo changes on all database objects including blockchain tables.
  • Blockchain Retention policies depends on system time and any changes to systems time must be audited.
  • Max number of user column allowed are 980
  • Blockchain tables doesn’t allow or support below operations
Column level restrictions
o Adding, dropping, and renaming columns
o Dropping partitions

Row level restrictions
o Update or merge rows
o Defining BEFORE ROW triggers that fire for update operations are not allowed.

Table level restrictions
o Truncate table
o Inserting data using parallel DML
o Sharded tables
o During distributed transactions, Inserting data into a blockchain table using Active Data Guard DML redirection is not supported
o Direct-path loading
o Flashback table
o Cannot convert a regular table to a blockchain table or vice versa.
o XA transactions

Database level restrictions
o Export and Import can be done as regular tables, without the system-generated hidden columns.
o Creating blockchain tables in CDB or application root
o Creating Oracle Label Security (OLS) policies
o Using the DBMS_REDEFINITION package for Online redefinition
o Creating Oracle Virtual Private Database (VPD) policies
o When using Transient Logical Standby and rolling upgrades, the DDL and DML on blockchain tables are not replicated and supported
o when using Logical Standby and Oracle GoldenGate, the DDL and DML on blockchain tables succeed on the primary database but are not replicated to standby databases
o Creating Automatic Data Optimization (ADO) policies

Thanks & Regards
https://oracleracexpert.com, Oracle ACE