Linux Containers – Container LInux: Core OS – a minimal linux? A quick overview: diskspace, mounts, commands, kernel, …

Virtualization techniques can be grouped into two categories
  1. os virtualization like VMware, Virtualbox, etc.
  2. container virtualization like Docker, etc.

Everybody is familiar with the first category. Creation of virtual machines is well known and most of us have created already tens or hundreds of such machines. (and deleted and lost them after some weeks). One of the benefits is, that it is easy to run additional machines on our laptops / workstations.
The second category (more...)

How to Checksum Downloads

As a DBA, in your time, you will need to download files such as Oracle binaries, patches, etc.  As a rule of thumb, you should always checksum you downloads, to ensure they are free of corruption.  In my example, I needed to download:

This is the Quarterly Full Stack Download Patch for Exadata, which is 10 zip files that (more...)

LEAP#335 MCP2200 LED Chaser (just because)

The MCP2200 USB-UART transceiver has 8 GPIO pins. Yes, you read that correctly. With such unexpected I/O capabilities, I feel obliged to do the only responsible thing: blink LEDs. Seven LED outputs and one input for a push-button to control direction of the “chase” sequence. As simple C program using the hidapi and we’re done! As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image

Choosing a password scheme for the database

In the Security Guide there is a section to assist you with the decisions about what rules you might want to have in place when users choose passwords, namely attributes like the minimum length of a password, the types of characters it must (and must not) contain, re-use of old passwords etc etc. The documentation refers to a number of pre-supplied routines that are now available in 12c to assist administrators.  This is just (more...)

How was Game Of Thrones S07 E05? Tweet Analysis with Kafka, BigQuery and Tableau

How was Game Of Thrones S07 E05? Tweet Analysis with Kafka, BigQuery and Tableau

I don't trust statistics and personally believe that at least 74% of them are wrong.... but I bet nearly 100% of people with any interest in fantasy (or just any) TV shows are watching the 7th series of Game of Thrones (GoT) by HBO.
If you are one of those, join me in the analysis of the latest tweets regarding the subject. Please be also aware that, if you're not on the latest episode, some (more...)

Jarvis Pizzeria: Collaborate in PCS

| Aug 17, 2017
An interesting aspect of working in Oracle Process Cloud Service with a team of three people is the fact that you need to collaborate and work together in the same “source”. However, where traditionally we are used to develop on our machine and merge source in repositories like Git, Bitbucket or Subversion, in the Cloud, we do not even see the source, let alone are able to merge it.
So, how does a team collaborate (more...)

Revising jQuery with Oracle APEX

A few years ago I managed to bust out a book that explored my experiences using jQuery within Oracle APEX to solve various problems, many originally explored when building some "backend" apps for use on tablets.

For those who've read my book, thank you and I hope it was useful to you.
(I also hope you read the revised chapter 9 on calling PL/SQL from JavaScript.)
Please let me know what you thought of (more...)

In Memory Session State – Simple Example

Not too long ago I encountered an interesting behaviour with session state, turns out not long after Dick Dral posted a very similar article that I had not yet seen.

Recently I encountered an even easier scenario.

I had a bunch of columns where I wanted to use the same prefix across all headers, but I wanted to define the value once, referring to it many times. I'm betting on the fact someone may (more...)

How do I share a URL to my APEX application?

What is the URL for my APEX application?  If I want to provide a URL to my APEX application to others, what URL do I give them?

Great questions!  I see this done incorrectly all the time inside of Oracle.  A person new to Application Express (APEX) will create an application or install a Productivity Application, run it, copy the full URL, and include the full URL in an email.  I encountered this today in (more...)

New Video of Oracle Security Vulnerability Scanning

I have just made a new video of a sample session using PFCLScan our vulnerability / security scanner for the Oracle database. In the video I show how easy it is to get started with PFCLScan and scan an Oracle....[Read More]

Posted by Pete On 17/08/17 At 01:50 PM

Build the Oracle APEX application: the framework

Over the years while developing Oracle APEX application, I noticed in every application I was following the same steps. It was a routine I followed over and over. For example: in every application I created a global page (page 0), enabled Feedback, ran the Advisor multiple times a week, used certain naming conventions etc.

A few years ago I wrote those steps in our APEX R&D development guide, so within our team we would be (more...)

How to obtain the Historical Database Total Used and Allocated Size from OEM Repository

From time to time, it’s useful to know the total allocated size of a database at OS level, how much of it has been used and what the maximum total size the database can grow to at OS level, see blog post:
How to obtain the Database Total Used, Allocated and Max Size

However, it’s also goo to know the historical size.  The below query will give you this from the Oracle Enterprise Manager (OEM) repository:


Diving Into Deep Links

I had another one of those eye-opening customer experiences recently.  I was engaged in a web conference with an Oracle customer discussing some UX extensibility features that come out of the box with HCM Cloud Applications.  During the conference, we got into a brief demonstration that included utilization of some deep links. Went over pretty well, people got excited, we had a rousing exchange on the benefits of deep linking and I was feeling pretty (more...)

SQL Server 2012 and Changes to the Backup Operator Permissions

I’m off to Columbus, Ohio tomorrow for a full day of sessions on Friday for the Ohio Oracle User Group.  The wonderful Mary E. Brown and her group has set up a great venue and a fantastic schedule.  Next week, I’m off to SQL Saturday Vancouver to present on DevOps for the DBA to a lovely group of SQL Server attendees.  It’s my first time to Vancouver, (more...)

How to obtain the Database Current, Total and Max Size

From time to time, it’s useful to know the total current size of a database at OS level, how much of it has been used and what the maximum total size the database can grow to at OS level.

The below query will give you this:

SELECT round(sum(used_ts_size)/1024/1024, 2) total_used_db_size_tb,
 round(sum(curr_ts_size)/1024/1024, 2) total_current_db_size_tb,
 round(sum(max_ts_size)/1024/1024, 2) total_max_allocated_db_size_tb
(SELECT df.tablespace_name, (df.bytes - sum(fs.bytes)) / (1024 * 1024) used_ts_size,
df.bytes / (1024 *  (more...)

Oracle Java Cloud Service – Scaling and Cluster Setup for ADF

Last couple of weeks I was busy preparing to my OOW'17 session about estimating Java Cloud Service performance for ADF application. I was running stress tests against various JCS instance configurations to be able to create performance estimation methodology. I will describe this methodology on OOW, but here today will list key steps required to scale up JCS instance.

Let's assume you are running single cloud node with 1 CPU and 7.5 GB RAM. (more...)

LEAP#334 Exercising the MCP2200 USB-UART transceiver

The MCP2200 is a USB-to-UART serial converter device. It is getting a bit on the old side, only supporting USB 2.0, and all the software support provided is Windows-only. Nevertheless, I got hold of the MCP2200 Breakout Module to find out more. I was particularly intersted to see how far I could get under MacOSX, including configuration over the HID Interface. The answer is pleasantly: all the way! As always, all notes, schematics and (more...)

LEAP#333 Measure Thy Own Voltage

One of the issues with analogue measurements on the Arduino is that typically we assume an accurate 5V reference, and need to add fudge factors for a calibrated reading. Well, I borrowed some code and re-read the ADC part of the datasheet again, and there is a neat little trick for using the 1.1V internal voltage reference to measure (thus calibrate) the supply voltage. It works, but not without caveats - so although QI, (more...)

#orclapex Europe tour

From Tuesday, the 29. of August until the 02. September, I will meet the best experts around Oracle.

But first some background:
Last year I was in Sweden and held a presentation at a meetup in Stockholm about APEX. I met Mathias Magnusson an Oracle specialist who is organizing all kinds of Oracle usergroup events in Sweden. I was lucky to meet him again at DOAG 2017 and introduced him to Joel Kallman. During (more...)

SQLcl – the SQL*Plus plus a plus …

"euphoric: intensely happy or confident", @thatjeffsmith, ...

Just watched the video from @thatjeffsmith about SQLcl - and it is, indeed, worth the time. After looking that video, I'm pretty sure that SQLcl will replace SQL*Plus within months (if some more people 'spread the word').

Just a few keywords to make you curious:

  • SQLcl is available as 'standalone' download, but it is also already part of the latest SQLDeveloper 17.2. (more...)