Using DBMS_PARALLEL_EXECUTE

DBMS_PARALLEL_EXECUTE

We have a number of updates to partitioned tables that are run from within pl/sql blocks which have either an execute immediate ‘alter session enable parallel dml’ or execute immediate ‘alter session force parallel dml’ in the same pl/sql block. It appears that the alter session is not having any effect as we are ending up with non-parallel plans. When the same queries are run outside pl/sql either in sqlplus or sqldeveloper sessions the (more...)

Migrating tablespaces across endian platforms

T 4 HP-UX IA (64-bit)   Big 13 Linux x86 64-bit   Little[/code]

 

Set the tablespace EXAMPLE read only

 

 alter tablespace example read only;

Tablespace altered.

select file_name from dba_data_files;

+DATA/hpuxdb/datafile/example.352.886506805

EXEC SYS.DBMS_TTS.TRANSPORT_SET_CHECK(ts_list=>'EXAMPLE', incl_constraints =>TRUE);

PL/SQL procedure successfully completed.

SELECT * FROM transport_set_violations;

no rows selected

Export the data using the keywords transport_tablespaces

 

expdp directory=data_pump_dir transport_tablespaces=example dumpfile=hpux.dmp logfile=hpux.log Starting "SYS"."SYS_EXPORT_TRANSPORTABLE_01": /******** AS SYSDBA

Processing object type TRANSPORTABLE_EXPORT/PLUGTS_BLK
Processing  (more...)

Creating standby database inc DG Broker and 12c changes

I thought I would refresh my knowledge of creating a standby database and at the same time include some DataGuard Broker configuration which also throws in some changes that came along with 12c

Overview

Database Name QUICKIE host server 1 ASM disk

Database Name STAN host server 2 ASM disk

Create a standby database STAN using ACTIVE DUPLICATE from the source database QUICKIE

 

QUICKIE =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = server1)(PORT  (more...)

Startup PDB databases automatically when a container is started – good idea?

I posed a note on the Oracle-L Mailing list around pluggable database and why they were not opened automatically by default when the container database was opened. The post is below

I am trying to get my head around the thing about how pluggable databases react after the container database is restarted.

Pre 12.1.0.2 it was necessary to put a startup trigger in to run a ‘alter pluggable database all open;’ command (more...)

Issues around recreating a standby database in 12c

When you create a database in 12C it now creates a resource in HAS/CRS , which isn’t a problem

However, when you come to recreate a standby database, probably because it has got such a big lag that it is quicker to recreate than recover the log files, then you will see the following error message :-

 

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of Duplicate Db command  (more...)

Large audit trail table causes high db activity – especially when using OEM

On various databases, apparently unrelated we have noticed high activity that seems to be associated with the query below. The quieter the database the more the query stands out.

 

SELECT TO_CHAR(current_timestamp AT TIME ZONE 'GMT', 'YYYY-MM-DD HH24:MI:SS TZD') AS curr_timestamp, COUNT(username) AS failed_count, TO_CHAR(MIN(timestamp), 'yyyy-mm-dd hh24:mi:ss') AS first_occur_time, TO_CHAR(MAX(timestamp), 'yyyy-mm-dd hh24:mi:ss') AS last_occur_time
FROM sys.dba_audit_session
WHERE returncode != 0 AND timestamp >= current_timestamp - TO_DSINTERVAL('0 0:30:00')

oem1

The detail of the audit table is that it contains 73M records (more...)

Cloud agent set to DEBUG causing out of memory errors

The following technical detail was put together by a colleague John Evans and have taken it , with his permission, and wrapped some more detail around it as it seemed to be of real value to anybody who might have upgraded an agent to 12.1.0.4

Following an upgrade of the EM agent from 12.1.0.2 (or 12.1.0.3) to 12.1.0.4 after about 90 days of (more...)

One million blog views reached

This morning I will pass the 1 million mark for hits on this blog. My first post was written in 2008 and I remember being quite pleased with myself when I reached 5000 hits, I never dreamt of getting 1 million.

The post with the most number of hits is https://jhdba.wordpress.com/2009/05/19/purging-statistics-from-the-sysaux-tablespace/

One that I get still comments on now saying how well it explains what the SQL92_SECURITY parameter actually does

https://jhdba.wordpress.com/2009/11/23/what-does-the-sql92_security-parameter-actually-do/

(more...)

Discrepancies in v$parameter default values in 12c

In my last blog about security parameters I mentioned I had found some oddities in the default values for parameters in 12.1.0.2, this is a more in-depth analysis of my findings.

Taking the parameter SEC_RETURN_SERVER_RELEASE_BANNER as an example.

Prior to 12c the default value for this parameter was ‘FALSE’, whereas the documentation for 12c (https://docs.oracle.com/database/121/REFRN/refrn10275.htm) states that the default is ‘TRUE’.

To confirm this, I made a (more...)

Security parameters in 11G and 12C

There are 5 parameters that are all prefixed with ‘sec’ in an 11g and 12c database. Actually that is a lie because one is now deprecated in 12c. They are all, as you might guess related to security. This blog is about changes in the default values and some thoughts about whether or not the default value is appropriate or not.

SEC_CASE_SENSITIVE_LOGON TRUE in 11GR1 , 11GR2, DEPRECATED IN 12C
SEC_MAX_FAILED_LOGIN_ATTEMPTS default 11GR1,11GR2=10, 12c=3
SEC_PROTOCOL_ERROR_FURTHER_ACTION (more...)