Oracle Enterprise Manager Cloud Control 13c Release 3 ( : Installation & Upgrade

Cloud Control 13c (13.3) was released a few days ago, but from what I can see the documentation hasn’t been made available yet. Despite this I had a go at installing it using the instructions for 13.2, and with a couple of small exceptions it was similar, which wasn’t surprising. The upgrade from 13.2 to 13.3 was similar to the previous upgrade from 13.1 to 13.2 also.

I’ve added (more...)

12C Grid – GENO process causes high CPU usage

This is an interesting bug which has affected a number of our databases  – perhaps because we are not patched to the latest levels in every case.
The MoS note is this one – Patch 20373598: GEN0 TIMEOUT ACTION ALWAYS TRY TO INITIALIZE OCR CONTENT    p20373598_121022_Linux-x86-64
fixed in Bug 22291127 (Apr 2016) Database Patch Set Update (DB PSU)
Here is view of top showing how a server looks (more...)

CONTAINERS clause and LONG columns

We were working on a monitoring script using HIGH_VLAUES in CDB_TAB_PARTITIONS and found the HIGH_VALUE column is missing in the CDB_TAB_PARTITIONS while the column is existing in DBA_TAB_PARTITIONS. Couldn’t find any reference in Oracle documentation (may be need a better search!) Why the column is missing in CDA view. Looking at the CDB_TAB_PARTITIONS view definition, oracle is using CONTAINERS clause to fetch all partition information, except the column HIGH_VALUE

SQL>; select TEXT from dba_views  (more...)

Validate FK

A comment arrived yesterday on an earlier posting about an enhancement to the truncate command in 12c that raised the topic of what Oracle might do to validate a foreign key constraint. Despite being sure I had the answer written down somewhere (maybe on a client site or in a report to a client) I couldn’t find anything I’d published about it, so I ran up a quick demo script to show that all Oracle (more...)

Historic Stats

If you want to examine historic object stats Oracle gives you a few procedures in the dbms_stats package to compare sets of stats captured at two different time periods, but there’s no view that you can query to get an idea of how a table’s stats have changed over time. This is a problem that can be addressed when you discover two things:

  • There are views to report pending table, index, column and histogram stats.
  • (more...)

Why Automation Matters : ITIL

ITIL is quite a divisive subject in the geek world. Once the subject is raised most of us geeks start channelling our inner cowboy/cowgirl thinking we don’t need the shackles of a formal process, because we know what we are doing and don’t make mistakes. Once something goes wrong everyone looks around saying, “I didn’t do anything!”

Despite how annoying it can seem at times, you need something like ITIL for a couple of (more...)

MobaXTerm 10.8

About a week ago MobaXTerm 10.7 was released, and today we got MobaXTerm 10.8. 🙂

The downloads and changelog are in the usual places.

Now I’ve moved back to Windows full time this is what I use at work and at home. Happy days! 🙂



MobaXTerm 10.8 was first posted on July 7, 2018 at 10:18 am.
©2012 "The ORACLE-BASE Blog". Use of this feed is for personal non-commercial use (more...)

hostname in Oracle Linux 7.x ändern

Möchte man in Oracle Linux Version 7.x (ich nutze hier im Beispiel OL 7.5) den „hostname“  ändern, hat man drei Möglichkeiten:

NetworkManager text user interface tool

# nmtui

Menüpunkt auswählen Namen setzen abspeichern fertig

NetworkManager command line tool „nmcli“ 


# nmcli general hostname

Setzen des hotsname mit

# nmcli general hostname o2


Das „hostnamectl“ Kommando

# hostnamectl set-hostname o2 --static

Überprüfen kann man seine „Arbeit“ wie folgt

# hostnamectl status
Static hostname: o2

Question Time

It’s that time of year again – the UKOUG Tech conference is approaching and I’m organising a panel session on the Cost Based Optimizer.

As usual I’ll be asking Christian Antognini, Nigel Bayliss, Maria Colgan and a special guest panellist (maybe David Dimbleby will be able to find the time now that he’s retired from chairing his own panel); and Neil Chandler and Martin Widlake will be volunteering to take on their inimitable roles as (more...)

Data Modeling, Dates and DAX

Presenting data in the format to ease visualization is required for any BI product.  Power BI provides much of this with Data Analysis Expressions, (DAX).   As a DBA, I admit to cringing every time a reference was made how similar it is to functions in Excel or other non-database platforms.  I’m a DBA and I naturally am going to see data at a much larger, more complex level.  I love (more...)

Complex materialized views and fast refresh

Just a quick discovery that came across the AskTOM “desk” recently. We have an outstanding bug in some instances of fast refresh materialized views when the definition of the materialized view references a standard view.

Here’s a simple demo of the issue – I’ll use a simplified version of the EMP and DEPT tables, linked by a foreign key in the usual way:

SQL> create table dept(dept_id number(10) primary key, dname varchar2(20));
Table created.
SQL>  (more...)

VirtualBox 5.2.14

While I was away VirtualBox 5.2.14 was released.

The downloads and changelog are in the usual places.

I’ve done the install on my Windows 10 laptop and on my Windows 10 PC at work and both worked fine.

I also pulled down the latest version of Vagrant (2.1.2) and did a complete rebuild of some stuff. From what I can see it’s all good. 🙂



VirtualBox 5.2.14 was (more...)

Index Column Order – Impact On Index Branch Blocks Part II (The Weeping Song)

In Part I, I discussed how the order of columns in an index makes no real difference to the effectiveness of the index if all columns are referenced via equality predicates. If the leading column has a high number of distinct columns, it might result in less necessary data within index branches as less data […]

I Got Here On My Own

Click bait worthy title, eh? 🙂

That’s what I thought after I read the article from the Harvard Biz Review with the lead in comment, “Women who have already made it to the top say that the only person who will get you there is yourself.”  I found this utterly misleading and the article missing many of the important areas, proving this incorrect.  We are highly critical of women and we’re uncomfortable with women’s ambition, (more...)

Oracle Code : Paris – The Journey Home

I left Oracle Code : Paris a little after 5 PM. I got in the taxi, got a few miles down the road and realised I had left my phone charging in the speaker room. Doh! I got the taxi to turn round so I could pick it up. Phone in hand, I got back in the taxi and off we went…

The roads were a lot slower the second time round, but I kept (more...)

Oracle Code : Paris 2018

Oracle Code : Paris started with a short walk from the hotel to the venue. After signing in it all began…

The first session of the day was a keynote by Lonneke Dikmans called “What Happened to My Order? The Need for Orchestration in Modern Architectures”, comparing BPEL orchestrations with orchestrations and choreography used in microservices and serverless architectures. It was a really good introduction to the concepts.

Next up was James Allerton-Austin with “Building (more...)

One-off Patch Frustration

Lately I started patching a client’s database ( to the latest PSU (180417). This is a RAC environment with streams and all kind of other features, so over the time we hit quite a lot of different bugs. When we planned this PSU (we installed the bundle patch version), we added about 7 one-off patches … Continue reading One-off Patch Frustration

Standard Edition–different optimizer but still cool

One cool technique that the optimizer can employ is the BITMAP CONVERSION TO ROWIDS method to take advantage of B-tree indexes in a means that we would normally associate with a bitmap index. This can be particularly useful with multiple predicates on individually indexed columns because it lets us establish the rows of interest before having to visit the heap blocks.  Here’s an example of that in action, even when the indexes in question (more...)

Announcement: New Europe Seminar in Brussels, Belgium 27-28 September 2018

Due to popular demand, I’ll be running another of my acclaimed seminars in Europe later in the year, this time in Brussels, Belgium on 27-28 September 2018. This is a must attend seminar of benefit to not only DBAs, but also to Developers, Solution Architects and anyone else interested in designing, developing or maintaining high […]

Oracle Code : Paris – The Journey Begins

It was a normal start to the day. I woke up with my regular work alarm, packed and got a taxi to the airport.

The drive was quick and the taxi driver was interesting, which helps. I couldn’t do online check-in because my ticket was with Air France, but the flight was Flybe. Neither website would let me check in online. I was dreading an epic queue, but fortunately the airport was quiet. Even so, (more...)