Add user as sudoer

Somebody asked why adding a user to the wheel group in didn’t enable them as a sudoer, as qualified in my earlier Fedora post. The reason is that you also need to modify the primary group in the /etc/passwd file to specify the Group ID value for the wheel group as the primary group of the designated student user.

You can identify the Group ID with the following command:

cat /etc/group | grep wheel


Find files with errors

My students wanted a quick solution on how to find the log files that contain errors. That’s a simple line of code in Linux if you want any Oracle errors that start with ORA-:

find . -type f | xargs grep -i ora\-

It takes only a moment more to look for errors starting with ORA- or PLS-, like:

find . -type f | xargs grep -i -e ora\- -e pls\-

The latter might return (more...)

Convert JSON with PHP

Sometimes I get poorly thought or just naive questions. That is naive questions because they didn’t read the documentation or don’t understand the semantics of a given programming language. The question this time said they tried to implement what they found on a web page but their sample json_decode function example failed after they followed directions.

Surprise, it didn’t fail because they followed directions. They overlooked part of the example because they didn’t understand how (more...)

Chrome on Fedora 27

Installing Chrome wasn’t as easy just running the yum utility. You need to download it from the following website.

When you try to use the rpm utility to run it, you’ll get the following errors:

warning: google-chrome-stable_current_x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID 7fac5991: NOKEY
error: Failed dependencies:
        /usr/bin/lsb_release is needed by google-chrome-stable-74.0.3729.131-1.x86_64 is needed by google-chrome-stable-74.0.3729.131-1.x86_64
        liberation-fonts is  (more...)

PostgreSQL Native OS X

Started playing around with a native installation of PostgreSQL on my Mac OS X. I navigated to the PostreSQL page to download the program. I downloaded and installed the PostgreSQL Version 11.

Then, I had to connect as the postgres user and start the server. You do that by opening a Terminal, assume the role of superuser root, and then connect as the postgres user. The commands are:

sudo sh
su - postgres


iPhone & Snowblower

What happens when your 16 year old doesn’t know he has a hole in his pocket, the iPhone slips down his pant leg unnoticed, and he runs over the device with a snowblower. It’s called instant shredded iPhone. You think that’s bad news but that’s why I purchased AppleCare for the device.

Then, you call Apple and discover that unless they can find and read the IMEI number from a chip, there is no warrantee (more...)

Variable Scope

Microsoft SQL Server provides T-SQL with the ability to assign values from the queries to local variables. While T-SQL returns a SELECT-list, there are rules for how you can assign the SELECT-list values. The process is more or less an all or nothing approach when assigning values to a local variable. The rule is quite simple for scalar variables because the SELECT-list may contain multiple values but assignments must be made one (more...)

Upgrade pip Utility

You should always have the most current version of pip installed when working with Python. You can upgrade the pip utility with the following command:

sudo pip install --upgrade pip

It should print the following to the console:

Collecting pip
  Downloading (1.3MB)
    100% |████████████████████████████████| 1.3MB 971kB/s 
Installing collected packages: pip
  Found existing installation: pip 9.0.3
    Uninstalling pip-9.0.3:
      Successfully uninstalled pip-9.0.3
Successfully installed pip-18.1

Upgrade to macOS 10.14

It was a forced upgrade to run TurboTax. The upgrade was simple because I work on a Mac Pro 2012 (with 64 GB of memory and 12 TB of storage. As you can tell from Apple’s support article, you must upgrade the video card.

I bought the SAPPHIRE Radeon PULSE RX 580 8 GB GDDR5 but when I went to install it after upgrading to macOS 10.13 (High Sierra), there was a catch. (more...)

Python & Oracle 1

While Python is an interpreted language, Python is a very popular programming language. You may ask yourself why it is so popular? The consensus answers to why it’s so popular points to several factors. For example, Python is a robust high-level programming language that lets you:

  • Get complex things done quickly
  • Automate system and data integration tasks
  • Solve complex analytical problems

You find Python developers throughout the enterprise. Development, release engineering, IT operations, and support (more...)