I was faced with a very strange situation.

When using SETENV (ORACLE_SID = db01), replicat ABEND with  OGG-00664  OCI Error beginning session (status = 1034-ORA-01034: ORACLE not available

When using SETENV (ORACLE_HOME=/u01/app/oracle/product/, replicat starts without any issues.

I know what you are thinking, why not set both ORACLE_SID and ORACLE_HOME and you are correct since this is best practices.

The client already knows this and wanted to troubleshoot why it was failing?

Any ideas? (more...)

A neural network scoring engine in PL/SQL for recognizing handwritten digits

Topic: In this post, you will find an example of how to build and deploy a basic artificial neural network scoring engine using PL/SQL.

On An Average Day

"There are other advantages," continued the child. "For instance, if one rat were cornered by nine cats,
on the average, each cat would be ten percent rat and the rat would be ninety percent cat. If you happened
to be a rat, you can see how much nicer it would make things."
-- Norton Juster, The Phantom Tollbooth

Recently an interesting question appeared on “Ask Tom” with regard to the ‘average’ between two dates. (more...)

Different names for 12c CDB

Truthfully, I am feeling a little lazy to write a nice blog.

Configuring listener.ora and tnsnames.ora, varying names for database, connecting to database.


db_name                              string      tmnt
db_unique_name                       string      tmnt_a
instance_name                        string      tmnt01

ADR Home /u01/app/oracle/diag/rdbms/tmnt_a/tmnt

Services Summary...
Service "april" has 1 instance(s).
  Instance "tmnt01", status READY, has 1 handler(s) for this service...
Service "tmnt" has 1 instance(s).
  Instance "tmnt", status UNKNOWN, has 1 handler(s) for this service...
Service "tmnt_a" has 1 instance(s).

Data Guard Broker : 11g and 12c

vault-154023_640I’ve been using standby databases, on and off, since Oracle 8i. I first wrote about Data Guard for Oracle 9i. I’ve had an article on 11gR2 Data Guard for ages, but up until recently I’ve always used the manual setup.

We’ve got a project coming up that *may* use Data Guard and *may* be installed by a 3rd party, so I figured I better get up to speed with the Data Guard Broker, in case they (more...)

ORA-15418: Appliance Mode Not Supported For Compatible.asm

The other day, I was upgrading a compatible.asm parameter to 12.1 on Exadata and I faced this error for the first time :

View the code on Gist.

Indeed, a diskgroup can have this parameter set to TRUE or FALSE :

View the code on Gist.

I then found this note on Metalink : EXADATA : What Is Oracle ASM appliance.mode Attribute (Doc ID 1664261.1) which explains that starting from Exadata (more...) New Features

Just a quick note as I play with CDB/PDB.

No more triggers!

PDB State Management Across CDB

select con_name, instance_name, state from DBA_PDB_SAVED_STATES;
alter pluggable database PDB1 SAVE STATE;
alter pluggable database ALL SAVE STATE;
alter pluggable database ALL DISCARD STATE;
alter pluggable database ALL OPEN;

startup force mount exclusive restrict;
drop database;

Drop database still does not clean up ADR.

$ sysdba

SQL*Plus: Release Production  (more...)

Create 12c CDB using dbca or sqlplus ???

How do you typically create database, using dbca or sqlplus?

I am still surprised with all the bloatware added for creating database using dbca.

Also, is there a reason to prefix PDB with pdb?

$ ll
total 28
-rw-r--r--. 1 oracle oinstall  801 Jul 19 12:59 cr_cdb.sql
-rw-rw----. 1 oracle oinstall 1544 Jul 19 13:06 hc_tmnt.dat
-rw-r--r--. 1 oracle oinstall  216 Jul 19 12:48 inittmnt.ora
-rw-r-----. 1 oracle  (more...)

em13c and ie11

So this week I've been doing some more stuff with cloud control 13c and came across a small issue when trying to use it with ie11.

With firefox everything was working fine but with ie i would just get a kind of generic error message that really told me nothing about what was actually wrong.

To confuse things we were running the browser with the remote app PaaS service from Oracle - for those of (more...)

It’s Us Against Them

As DBAs we are usually located in the middle between the IT (sysadmins, storage, network) and the development. Some of my best friends are sysadmins and developers (well, friends anyway), but I still want to dedicate this post to let off some steam about them. I hear many complaints from DBAs about sysadmins (and I […]

VirtualBox 5.0.26

If you’ve not taken the plunge and upgraded to VirtualBox 5.1, you might be interested to know that VirtualBox 5.0.26 has been released.

Downloads and changelog are now listed under the old builds.

In case you are wondering, I’ve been running VirtualBox 5.1 on Mac, Windows 7 and Oracle Linux 6 hosts since its release. As yet, not problems.



VirtualBox 5.0.26 was first posted on July 19, (more...)

Oracle DIRECTORY access on OS layer

Oracle DIRECTORY objects are very nice to handle access for external tables or other procedures.
It just can be challenging to enable proper access to those files for other users than the database user (I call it oracle here).

If there are any concerns to allow any access to the databases host (except for DBAs and OS admins) it get's tricky fast.

One possibility is to use a NFS mount and make the directory available (more...)

ORA-39710 and ORA-00704

I tried to use dbua to upgrade a database from Oracle to Oracle Part way through, my PC lost connection with the UNIX server hosting the database. I tried to connect to the database but got an ORA-39710 so I forced the database to close with shutdown abort:

NLFINUT1 /export/home/oracle > sqlplus /

SQL*Plus: Release Production on Mon Jul 18 14:03:08 2016


Delphix Express- Adding XE DSource

For those of you that downloaded and are starting to work with Delphix Express, (because you’re the cool kids… :)) You may have noticed that there is an Express Edition Oracle 11g database out there you could use as a Dsource, (source database for Delphix to clone and virtualize…)


If you’d like to work with this free version with your Delphix Express environment, these are the steps (more...)

Using UDev to configure ASM disks

This is a small article on using UDev on RHEL 7. I have a virtual box with RHEL 7 and I am configuring ASM diskgroups.

Before we configure ASM diskgroups, we need to have disks/partitions available at OS level and those should be recognized by ASM. Oracle provides a utility called ASMLib which can be installed and used very easily to configure disk/partitions at OS level.

ASMLib stamps the header of partitions/disk at OS level (more...)

Video Tutorial: XPLAN_ASH Active Session History – Part 8

The next part of the video tutorial explaining the XPLAN_ASH Active Session History functionality continuing the actual walk-through of the script output.

More parts to follow.

How To Configure Exadata Database Machine in Enterprise Manager Cloud Control 13c (OEM13c)

I have followed the steps in Oracle Documentation link: to configure Exadata Database Machine in OEM13c. If you want to configure your Exadata in OEM13c you have to follow the above mentioned link. In this post I will share the mandatory steps for configuration, and some of the issues which I faced while configuring the Exadata…

GoldenGate and Netwworking

I have never delved into networking for GoldenGate since things just work. Due to security tightening, telnet is no longer available to verify opened port.

What’s to follow is a demo for ports being listened by GoldenGate when manager started and ports listened and when PUMP Extract is started as part using DYNAMICPORTLIST.

Also, how to test opened port using (nc – arbitrary TCP and UDP connections and listens)

Both source and target are running on the (more...)

Truncates and Sequences Replication in Oracle GoldenGate

We use the terms DDL and DML in our DBA life with Oracle all the time. The first stands for Data Definition Language and it is about Data Definition changes. The latter is about manipulation with your data itself, and stands for Data Manipulation Language. When we speak about replication of our data by replication tools between Oracle databases, we generally either enable DDL, work only replicating DML, or do it for both together. In (more...)

Oracle 12c Learning Series: Automatic Data Optimization – ADO

I am starting Oracle 12c learning series, where I am planning to publish multiple articles on Oracle 12c new features. I hope these articles will be helpful to DBAs aspiring for OCP 12c certification and also others who are planning to implement these features in there databases.

This is a very long post about ADO – Automatic Data Optimization, which is one of the ILM strategy to manage aging data. So please be patient while reading this article. This article provides end-to-end details (more...)