RegExp: Constraint to prevent spaces at the beginning or end.

Even though a space is a regular character, the client didn't want spaces at the beginning or end of a string. Any spaces in the middle were fine.
Of course this could be handled by the application, but it must also be implemented in the database. Using a check constraint with a regular expression will prevent the end user from entering unwanted data.

To try things out, let's just start with a simple table with (more...)

How Many ASM Disks Per Disk Group And Adding vs. Resizing ASM Disks In An All-Flash Array Environment

I recently posted a 4-part blog series that aims to inform readers that, in an All-Flash Array environment (e.g., XtremIO), database and systems administrators should consider opting for simplicity when configuring and managing Oracle Automatic Storage Management (ASM).

The series starts with Part I which aims to convince readers that modern systems, attached to All-Flash Array technology, can perform large amounts of low-latency physical I/O without vast numbers of host LUNs. Traditional storage (more...)

An introduction to Oracle PL/SQL for beginners

PL/SQL offers the entire suite of structured programming mechanisms, such as condition checking, loops, and subroutines, as shown in the following figure. (read more)

Conference Report: NoCOUG 2016 summer conference at Chevron

The Northern California Oracle Users Group (NoCOUG) is a volunteer-run 501(c)(3) organization and the longest-running Oracle users group in the world. It organizes a full-day conference every quarter and publishes a quarterly Journal. The summer conference at Chevron was the 119th quarterly conference organized by NoCOUG.(read more)

A day in the life of a problem solver

P.O.I.S.E.D. is the acronym I invented for the performance tuning method described by Chris Lawson in The Art and Science of Oracle Performance Tuning; it stands for Problem, Observation, Interpretation, Solution, Execution, and Documentation.(read more)

An excellent review of where we are, where it all came from, and where we are going‏

About the book he reviewed for the August 2016 issue of the NoCOUG Journal, Brian had this to say: “You should read this book. If you are starting out in a database-related career—which I think includes most, if not all, programming jobs—or if you are changing fields within the broader database field, the information in this book will be very helpful in the interview and on the job. I learned a great deal about things (more...)

Join me for the Reactive Microservices Roadshow

What are the benefits of the Reactive Manifesto and the Microservices approach, especially for those who want to fundamentally modernize their business? I will discuss this at the free event „Reactive Microservices Roadshow“, on 28th September in Berlin. The event is hosted by codecentric AG and Lightbend. There will be three talks which walk you through the most important parts.

Reaktive Mircroservices with Akka (Heiko Seeberger)
The Reactive Manifesto defines essential qualities which (more...)

Lightbender at JavaOne 2016

It's only short 16 days until the Java community is starting to travel to San Francisco again. The annual family gathering at JavaOne is the place to be and it's time to get a little excited about attending once again. This year, Lightbend is a bronze sponsor and I am excited to be one of the featured speakers! A lot is going to happen during the week and you have to plan your schedule accordingly (more...)

Resizing ASM Disks On Modern Systems. Real Application Clusters Doesn’t Make It Any More Difficult. An XtremIO Example With RAC.

My recent post about adding space to ASM disk groups by resizing them larger, as opposed to adding more disks, did not show a Real Application Clusters example. Readers’ comments suggested there is concern amongst DBAs that resizing disks (larger) in a RAC environment might somehow be more difficult than in non-RAC environments. This blog entry shows that, no, it is not more difficult. If anything is true it is that adding disks to ASM (more...)

PeopleSoft Partner of the Year

I would like to borrow a few minutes of your time to ask a quick favour. If you haven’t already, could you please vote ‘Gold’ for Cedar in the UK PeopleSoft Partner of the Year competition.

Here’s why I believe we’re worth your vote:

  • We’ve been serving PeopleSoft customers for 20+ years, and in each of the last few years we’ve worked with more than 40 clients
  • We’re active members of UKOUG, with (more...)

Fix Interactive Report headers issue when using a Region Display Selector

When you have multiple Interactive Reports (IR) on your page and use a Region Display Selector to mimic tabs, you might notice some weird behaviour in the IR headings if you switch tabs. The headings are not positioned correctly and you get an extra empty row under the headings. It just looks weird and ugly. But if you resize your browser window, it all looks fine again (until you switch to another tab..)

Are analytic RDBMS and data warehouse appliances obsolete?

I used to spend most of my time — blogging and consulting alike — on data warehouse appliances and analytic DBMS. Now I’m barely involved with them. The most obvious reason is that there have been drastic changes in industry structure:

Presenting at Oracle Open World 2016


Just a short post to announce that I’ll be presenting an User Group Forum session. Thanks ODTUG!

SQLcl: A Modern Command Line Interface to the Oracle Database [UGF5641]

“In this session learn about the new Java-based command line interface that takes advantage of Oracle SQL Developer’s scripting engine. It delivers a modern command line interface that is backward compatible with SQL*Plus but also introduces new commands and features that have been missing for a long (more...)

Smarter DG Broker in Oracle 12c

In Oracle 11G, DG Broker needed to be told whether the standby database was physical or logical. The command to add database in 11G was something like this:



Oracle 12c is definitely smarter and can figure it out on its own. The “ADD DATABASE” syntax is simpler:

DGMGRL for 64-bit Windows: Version – 64bit Production

Copyright (more...)

Maven builds for SOA Composites with BPEL Java embedding and Java class

Enviornment: Oracle SOA Suite 12.2.1

Sample Application:
(Git clone or use the download option from here: )

 A BPEL component has a Java embedding that in turn calls a Java class method (under the usual SCA-INF/src)

This works and builds find using JDeveloper, but the oracle-soa-plugin for maven seems to have a few known issues (see references for one of them) that cause builds for (more...)

Creating an APEX plugin for an Oracle JET component – Part 2

In my previous blogpost I showed how you can embed an Oracle JET component in your APEX application. Now it is time to make a plugin out of the wisdom we gained doing so.
First of all a disclaimer. My intention is to make this plugin and the inner workings as simple as possible. So you can add a lot more functionality, checks etc and therefore add complexity. But this is intended to be as (more...)

Grid Infrastructure 12c installation fails because of 255 in the subnet ID

I was doing another GI cluster installation last month when I got really weird error.

While was running on the first node I got the following error:

2016/07/01 15:02:10 CLSRSC-343: Successfully started Oracle Clusterware stack
2016/07/01 15:02:23 CLSRSC-180: An error occurred while executing the command '/ocw/grid/bin/oifcfg setif -global eth0/ eth1/' (error code 1)
2016/07/01 15:02:24 CLSRSC-287: FirstNode configuration failed
Died at /ocw/grid/crs/install/  (more...)

Building “Ready to Deploy” Oracle VM Templates

I’ve been playing a bit lately with Oracle VM on a few different platforms (ODA, Exalytics, Private Cloud Appliance) and was tasked with creating a good Oracle VM template image for Oracle Linux 7. Oracle makes templates available on eDelivery ( that present you with VM configuration questions on first boot, but those VM templates have a few limitations that make them hard to use:

  1. The templates have a minimal Linux installation, and are (more...)

SUBSTR Versus LIKE in Oracle 11.2

I was reading an old SQL tuning book which was printed in 2002. It said that a where clause with like could often use an index whereas a similar clause using substr could not. I wondered if this might still be the case in an Oracle database. To find out, I created a table:

SQL> conn andrew/reid
SQL> create table tab1 as
  2  select table_name from dba_tables
  3  (more...)

G-Cloud – Moving Your Oracle System to Amazon Web Services

G-Cloud was awarded a few weeks ago and we're glad to say that clckwrk were selected as a supplier in the areas of Infrastructure as a Service and Specialist Services.

The services we have on G-Cloud are specifically curated for implementing, moving and managing Oracle systems to the cloud. This is a quick guide for how to combine those services to migrate to the cloud. For public sector users of Oracle technology and applications this is the set (more...)