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Displaying posts with tag: unix (reset)
MySQL Transaction Scope

The idea of ACID transactions are a basic feature of SQL’s individual Data Manipulation Language (DML) commands, like the INSERT, UPDATE, and DELETE statements. Transactions across two or more tables are a natural extension of ACID compliance features provided by DML commands. However, they require a structured programming approach, like a store procedure or like API implemented in an imperative language.

Surprisingly, transaction management wasn’t covered well in Alan Beaulieu’s Learning SQL because he only provided pseudo code logic. While I thought troubleshoot some broken MySQL SQL/PSM logic would be a good learning experience for students, it wasn’t. So, I wrote this sample code to show how to achieve an all or nothing transaction across four tables.

The code for this example on transaction management lets you perform the important tasks necessary to effect transaction …

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Node.js & MySQL

These are my notes for creating a small Node.js application that queries a MySQL database. The post will show you how to:

  1. Configure your Node.js development directory.
  2. Build a small application to test a MySQL connection.
  3. Build a small application that connects to the MySQL database and queries data.

This blog post assumes you’ve performed a global install of Node.js on a Linux server. If you’re unfamiliar with how to perform a global Node.js installation, I cover how to do it in this earlier blog post.

Before you write the Node.js applicaiton, you need to setup a db developer directory. Then, create a node_modules symbolic link to the /usr/local/lib/node_modules directory in the db directory. You can use the following command …

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MySQL Linux to Windows

My students want to transfer their course setup MySQL files from the Linux VM that I provide to Microsoft Windows 10. This post explains how because I found a couple small errors in the Google’d posts they would most likely see.

The first step is required because when I didn’t assign a name or domain to the the Fedora VM, which allows it to run as localhost on any student machine. In tandem, I didn’t assign a static IP address but opted for dynamic IP assignment. That means, the first step to securely copy the files requires you to find the assigned IP address. You can do that with the following Linux command:

ifconfig -a | grep 'inet[[:blank:]]' | head -1 | cut -c 14-30

It would return something like:

192.168.147.198

After you have discovered the IP address, you need to download PuTTy from their web site because includes the pscp (PuTTy …

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Apache on Fedora 30

There was an option during the Fedora 30 Workstation installation to add the Apache Web Server, but you need to set it to start automatically. Unfortunately, there was no option to install PHP, which I thought odd because of how many web developers learn the trade first on PHP with a LAMP (Linux, Apache, MySQL, Perl/PHP/Python) stack. You see how to fix that shortcoming in this post and how to install and test PHP, mysqli, and pdo to support MySQL 8.

Before you do that make sure you install MySQL 8. You can find my prior blog post on that here.

You set Apache to start automatically, on the next boot of the operating system, with the following command:

chkconfig httpd on

It creates a symbolic link:

Created symlink /etc/systemd/system/multi-user.target.wants/httpd.service → …
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“About the unix philosophy, and why I broke it – and then how I moved back to the old track”

I am always fascinated by the cleanliness of UNIX. One tool only should do one thing, but it has to be the best in that way. The operating system itself will glue all the modules together and give you a complex feel of a system, you don’t have to take care of huge, bloated software, don’t have to deal with mysterious bugs, which are appearing random. Just small bricks of clever software and the rest are on you.

Recently I broke this, and frankly, I am not sure if it was a bad decision, or not.

With MySQL, if you want a point in time recovery after a disaster, you should back up not only the database but the binary logs themselves, as I have mentioned it in my last blog post. I added a feature to the binlogstreamer: it can clean up the binary logs after a given amount of time.

Let’s see how many ways we have to get rid of the old, unwanted …

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About the unix philosophy, and why I broke it – and then how I moved back to the old track

I am always fascinated about the cleanliness  of UNIX . One tool only should do one thing, but it has to be the best in that way. The operating system itself will glue all the modules together and give you a complex feel of a system, you don’t have to take care of huge, bloated software, don’t […]

Add Gedit Plugins

Fedora comes with vim and gedit installed but the gedit installation is bare bones. You can update gedit to include supplemental Plug-ins with the following yum command as the root user:

yum install -y gedit-plugins

It generates the following log file:

Loaded plugins: langpacks, refresh-packagekit
mysql-connectors-community                                  | 2.5 kB  00:00     
mysql-tools-community                                       | 2.5 kB  00:00     
mysql56-community                                           | 2.5 kB  00:00     
pgdg93                                                      | 3.6 kB  00:00     
updates/20/x86_64/metalink                                  |  14 kB  00:00     
updates                                                     | 4.9 kB  00:00 …
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The USE Method: Unix 7th Edition Performance Checklist


PDP 11/70 front panel (similar to the 11/45)

Out of curiosity, I’ve developed a USE Method-based performance checklist for Unix 7th Edition on a PDP-11/45, which I’ve been running via a PDP simulator. 7th Edition is from 1979, and was the first Unix with iostat(1M) and pstat(1M), enabling more serious performance analysis from shipped tools. Were I to write a checklist for earlier Unixes, it would contain many more “unknowns”.

I often work on the illumos kernel, a direct descendant of Unix …

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Linus on Instantiation and Armadaification

I feel a sense of pride when I think that I was involved in the development and maintenance of what was probably the first piece of software accepted into Debian which then had and still has direct up-stream support from Microsoft. The world is a better place for having Microsoft in it. The first operating system I ever ran on an 08086-based CPU was MS-DOS 2.x. I remember how thrilled I was when we got to see how my friend’s 80286 system ran BBS software that would cause a modem to dial a local system and display the application as if it were running on a local machine. Totally sweet.

When we were living at 6162 NE Middle in the nine-eight 292, we got an 80386 which ran Doom. Yeah, the original one, not the fancy new one with the double barrel shotgun, but it would probably run that one, too. It was also …

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451 CAOS Links 2011.08.31

MapR and Funambol raise funding. VMware virtually supports PostgreSQL. And more.

# MapR raised $20m series B for its Hadoop distribution from Redpoint Ventures, Lightspeed Venture Partners and NEA.

# Funambol raised $3m in funding from previous investors HIG Ventures, Pacven Walden Ventures and Nexit Infocom.

# VMware launched vFabric Postgres as part of vFabric Data Director database-as-a-service launch.

# Citrix released a new edition of CloudStack, …

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