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Relational and Non-relational Data: PGSQL Phriday #005

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.

 

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Fix LXC network issues in Ubuntu 22.04

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?

 

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