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How to open .nrg Files?

A well-meaning person gives you a .nrg file and you will not invest in a piece of expensive bespoke software to read it. After all, you run free, open-source software and never have and never will pay for software. What to do with this stupid .nrg file?

Unix Utilies for Windows

If you want to install Perl on Windows or do anything vaguely sophisticated in the brain-dead command line shell of Windows (a.k.a. the DOS prompt), then you need a collection of commonly used UNIX utilities that can run under Windows.

I have put together such a collection of the most popular UNIX utilities and a few other command-line programs. Most of these are GPL-licensed (i.e. open source) and the remaining few are free-ware (but not open source). Either way, you can do with these programs whatever you want.

You can download the bundle of utilities from here.

These utilities are particularly useful for installing Perl on your Windows PC. Download Perl for Windows from http://www.activeperl.com.

Product Quickcode Generator

How to generate a Base36 quick code sequence using the SHA2 hash

On a 'slowish' 2GHz machine it can generate 20,000 quickcodes per minute. The spread of the resulting quickcodes is near-perfectly even, which means that substrings of the quickcode can be used to construct a hashed directory tree for holding, for example, the huge amount of product image files associated with a product catalog. Using a hashed directory tree is a quick and efficient method to host millions of separate files for quick, random access, as most file systems only perform optimally with less than 1,000 contained in a directory

This deterministic techique uses a hash of the sequential Integer Id of an item to generate a typical product quickcode for it, as found in many shopping catalogues. Example of how a quickcode is generated from its primary key integer Id:

1 => 8M9LFLN2
2 => HZ40H3K0
3 => 02LUJYQ2
etc..

You can download the Base36 Quickcode Generator test script, which demonstrates an implementation in Perl and MySQL.

Getting Oracle's SQLPlus Client to run on Linux

If you are running a Linux version that does not support RPM packages and you need to install Oracle's sqlplus client, you have two options to install it:

If you have a DEBIAN-based Linux distro, download the RPM package and convert it to a DEB package using the alien utility. This can get a little complicated and requires you to unpack the .rpm file and then rebuild the pack of files into a .deb file. And then install it using your preferred DEB package installer.
Download one of the .zip files from Oracle. Which ones, you ask? It is not obvious which ones to download and if you don't get the correct combination of files, you get errors such as
```
sqlplus: error while loading shared libraries: libclntsh.so.21.1: cannot open shared object file: No such file or directory
```
when you try to run sqlplus. Here is the installation recipe for a full-fat installation of SQLPLUS:
Read more: Getting Oracle's SQLPlus Client to run on Linux

Oracle DBMS_PIPE - why you should abandon it

A classical method of getting Oracle-based processes communicating with the outside world is by using the DBMS_PIPE package: Typically, we write to a pipe from an Oracle PL/SQL-based process, and then we continuously run an asynchronous Oracle PL/SQL process which reads the pipe and processes what it reads. A common use of DBMS_PIPE is for debugging, logging and launching external processes.

Oracle External Procedures

It is possible to call O/S commands or third-party programs from within SQL or PL/SQL with external procedures. This guide describes how to build, install and use such an ExtProc and shows an exploit on how to grant yourself Oracle sysdba rights. Think of an ExtProc as an Oracle root kit.

Oracle server construction guide on Linux

A step-by-step construction guide to install and configure a Linux server from scratch and how to then install the Oracle 10g RDBMS on it.

Controlling the Bull in Software Development

It's nearly 35 years now that I have been in the software production and integration business and as an IT consultant, I have witnessed the inner workings of many types of businesses that claim to run their businesses with the aid of software and teams that do software development and integration into the business. I am still regularly surprised how so many businesses, including some of the most venerable banks and public organizations that are accountable to tax-payers, haphazardly fail to deliver functional software solutions that serve the business in this day and age, when we already have so much cumulative experience to learn from.

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