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I'm moving files from one QNAP system to another, and I'm using rsync for this. It's preinstalled on a QNAP system. So far, so good.

To sync entire shared volumes, I want to exclude the '@Recently-Snapshot' and '@Recycle' entries - I don't want to sync the trash bin and I also don't want to sync entire snapshots.

The usual approach when using rsync is to just use the --exclude option.

rsync --exclude='@Recently-Snapshot' --exclude='@Recycle'

To my surprise this does not work. rsync on the QNAP does not complain, but also does not ignore the entries. Using escapes in front of the '@' doesn't work either. Ok, which version is the rsync program anyway?

[~] # rsync --version
rsync  version 3.0.7  protocol version 30
Copyright (C) 1996-2009 by Andrew Tridgell, Wayne Davison, and others.

Ouch, that is old. Very old. Released December 2009. Pretty sure QNAP did not fix all the bugs in there.

But according to the documentation, and the --help output, it accepts the --exclude option. Still not working though.

Ok, there is one more option: --exclude-from

I create a text file and add the two entries in there:

@Recently-Snapshot
@Recycle

And then I use the --exclude-from option to skip entries in these two directories:

rsync --exclude-from=/tmp/pattern.txt

This option works. At least something.

Summary: The rsync on a QNAP system does not accept the --exclude parameter, but the --exclude-from parameter works.

And for everyone asking why I don't use the integrated file copy: this one skips certain files, but I also want my dot files copied over.

For this month's #PGSQLPhriday, Grant Fritchey asks: What is the one thing you wish you knew while you learn PostgreSQL.

My preferred client for PostgreSQL is psql, and while it is very powerful I like a few features a most:

• \timing
• \watch

Both are internal commands in psql, \timing is there for a very long time, but got improved at some point. \watch came later, but is also there for a couple years now.

 

Continue reading "PGSqlPhriday #006: One Thing You Wish You Knew While Learning PostgreSQL: psql commands"

With people moving away from Twitter, mostly to Mastodon, discovering the new accounts became a problem.

For people in the PostgreSQL community I created a website which lists different social media accounts. This website is part of the "PostgreSQL Person of the Week" interview project, however the data source is dynamic, and stored in a different repository. This allows me to keep the repository for the website private, but publish the data for the social media links - this data is public anyway. The interview repository is private, because who wants to see upcoming interviews anyway? ;-)

The interview website is made with Hugo, a static website generator. Normally Hugo looks for content, templates, and other data in the current directory - my private repository.

As part of compiling the website, Hugo can fetch external data, either in JSON or CSV format. This is using the getJSON() and the getCSV() functions, which can be used in Shortcodes, as example.

 

Continue reading "Dynamic content in static websites in Hugo"

Someone at FOSDEM 2023 asked the question: "What happens when PostgreSQL rolls over the version number to 95? Will this cause problems like back then in Windows?"

What does that even mean? When Microsoft released the version after Windows 98, they opted for naming it Windows 10, not Windows 9. Because apparently a lot of code out there checks if the string starts with "Windows 9" and then assumes that the OS is one of the very old ones. This might not be the only such problem, as another blog article by Microsoft shows. Apparently they used "3.95" for the Windows 95 internal version, because lazy programmers.

You may also remember that there is already a "Postgres95", released around 1994 (shortly before Windows 95 was released). This was before the name was "PostgreSQL", and this is the first version which had SQL support. Before that, QUEL was the query language.

Enough history. And even though the release of PostgreSQL 95 is still a few years out, this raises two questions:

1. Does today's source code work (aka: compile, and pass tests) with version number 95?
2. Does your application work against version PostgreSQL 95?

 

Continue reading "PostgreSQL 95"

Ryan Lambert asks in this month's PGSQL Phriday:

• What non-relational data do you store in Postgres and how do you use it?
• Have you attempted non-relational uses of Postgres that did not work well? What was the problem?
• What are the biggest challenges with your data, whatever its structure?
• Bonus: How do you define non-relational data?

Looking over the many databases we operate at work, I can say that we are mostly a "relational shop". Almost every database we have uses relational structures, and does not attempt to go in on "full NoSQL", or "store non-relational data". Many of the databases are on the larger size, often in the hundreds of GB or even several TBs. We have good people in our dev teams who understand both PostgreSQL and SQL, and can develop a proper schema for the data, and write performant queries.

There are a few exceptions though, but at least for us it's only a small number. Whenever we retrieve or get data which comes in from web requests, we may store this as JSON, and then we use JSONb. Quite often however it's rather "storage as JSON", not "querying the JSON in the database". It's just more convenient to keep the data in JSON format all the way, instead of transforming it several times.

 

Continue reading "Relational and Non-relational Data: PGSQL Phriday #005"

Ran into a curios problem while updating the GitHub Actions Workflow for a project:

Run sudo lxc exec test-container --env DEBIAN_FRONTEND=noninteractive -- apt-get -y install -y openssh-client openssh-server openssh-sftp-server
Reading package lists...
Building dependency tree...
Reading state information...
openssh-client is already the newest version (1:8.9p1-3).
The following additional packages will be installed:
  libpsl5 libwrap0 ncurses-term publicsuffix python3-distro ssh-import-id wget
Suggested packages:
  molly-guard monkeysphere ssh-askpass ufw
The following NEW packages will be installed:
  libpsl5 libwrap0 ncurses-term openssh-server openssh-sftp-server
  publicsuffix python3-distro ssh-import-id wget
0 upgraded, 9 newly installed, 0 to remove and 0 not upgraded.
Need to get 1371 kB of archives.
After this operation, 7679 kB of additional disk space will be used.
Ign:1 http://archive.ubuntu.com/ubuntu jammy/main amd64 openssh-sftp-server amd64 1:8.9p1-3

...

Ign:9 http://archive.ubuntu.com/ubuntu jammy/main amd64 ssh-import-id all 5.11-0ubuntu1
Err:1 http://archive.ubuntu.com/ubuntu jammy/main amd64 openssh-sftp-server amd64 1:8.9p1-3
  Cannot initiate the connection to archive.ubuntu.com:80 (2620:2d:4000:1::19). - connect (101: Network is unreachable) Cannot initiate the connection to archive.ubuntu.com:80 (2620:2d:4000:1::16). - connect (101: Network is unreachable) Cannot initiate the connection to archive.ubuntu.com:80 (2001:67c:1562::18). - connect (101: Network is unreachable) Could not connect to archive.ubuntu.com:80 (185.125.190.39), connection timed out Could not connect to archive.ubuntu.com:80 (185.125.190.36), connection timed out Could not connect to archive.ubuntu.com:80 (91.189.91.39), connection timed out

...

E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/s/ssh-import-id/ssh-import-id_5.11-0ubuntu1_all.deb  Cannot initiate the connection to archive.ubuntu.com:80 (2620:2d:4000:1::19). - connect (101: Network is unreachable) Cannot initiate the connection to archive.ubuntu.com:80 (2620:2d:4000:1::16). - connect (101: Network is unreachable) Cannot initiate the connection to archive.ubuntu.com:80 (2001:67c:1562::18). - connect (101: Network is unreachable)
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
Error: Process completed with exit code 100.

For the tests, I'm spinning up a LXC container on the Runner, and then try to install software in it. This specific Runner is using Ubuntu 22.04 (new), and the network connection to archive.ubuntu.com is failing. Another Runner in the same workflow, using Ubuntu 20.04, is working fine. 20.04 was the old test setup, 22.04 is the new one. No other changes. But why is it suddenly failing?

 

Continue reading "Fix LXC network issues in Ubuntu 22.04"

If you use GitHub Actions to run Workflows and tests, you might have spotted this warning recently:

Node.js 12 actions are deprecated. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/. Please update the following actions to use Node.js 16: actions/checkout@v2

This warning means that GitHub will deprecate a certain action, which checks out the repository into the runner. This is going on since early 2022 and by summer 2023 they plan to upgrade all actions to v16.

 

Continue reading "GitHub Actions: Node.js 12 actions are deprecated"

If you use GitHub Actions to run Workflows and tests, you might have spotted this warning recently:

The `set-output` command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

This warning means that GitHub will deprecate a certain syntax which populates variables, and disables it by end of May 2023.

 

Continue reading "GitHub Actions: The `set-output` command is deprecated and will be disabled soon"

It was time to update my laptop, and I already knew that the update will bring Snap, and installs the Snap Firefox version. Along with many known problems. Previously the laptop was on 20.04 LTS, but this version is about to loose support.

I ran through the upgrade, and then added an Ansible Playbook to handle the Firefox installation, remove the Snap version and install the PPA version. Most of my laptop configuration is handled using Ansible Playbooks.

 

 

Continue reading "Install Firefox PPA version over Snap version"

Henrietta Dombrovskaya asks about Software Development and PostgreSQL. That's a very broad topic.

Not being a big developer for myself, and only occasionally submitting patches here and there, I nevertheless have a vast amount of data available on the topic: the "PostgreSQL Person of the Week" interviews! There are a few questions in the interviews which relate to this topic:

• Could you describe your PostgreSQL development toolbox?
• Which skills are a must have for a PostgreSQL developer/user?
• Do you use any git best practices, which makes working with PostgreSQL easier?
• Do you think PostgreSQL has a high entry barrier?
• What is your advice for people who want to start PostgreSQL developing - as in, contributing to the project. Where and how should they start?

And having 143 published interviews at this point, there is really interesting data about this topic. I picked two points which aim directly at developers:

 

 

Continue reading "PGSQL Phriday #004: PostgreSQL and Software Development"