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PostgreSQL 95

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?

 

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PostgreSQL @ FOSDEM 2020

The PostgreSQL Project is present with a booth at FOSDEM ever since 2007. Since 2008 we organize a Devroom, since 2013 we have our own PGDay on the Friday before FOSDEM. This year marks the 8th FOSDEM PGDay.

This blog post presents useful information about the PGDay, the booth and Devroom at FOSDEM.

 

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How long will a 64 bit Transaction-ID last in PostgreSQL?

At FOSDEM someone asked how long 64 bit Transaction-IDs will last.

To refresh: PostgreSQL is currently using 32 bits for the TXID, and is good for around 4 billion transactions:

fosdem=# SELECT 2^32;
  ?column?  
------------
 4294967296
(1 row)

That will not last very long if you have a busy database, doing many writes over the day. MVCC keeps the new and old versions of a row in the table, and the TXID will increase with every transaction. At some point the 4 billion transactions are reached, the TXID will overrun, and start again at the beginning. The way transactions are working in PostgreSQL, suddenly all data in your database will become invisible. No one wants that!

To limit this problem, PostgreSQL has a number mechanism in place:

  • PostgreSQL splits transaction ids into half: 2 billion in the past are visible, 2 billion in the future are not visible - all visible rows must live in the 2 billion in the past, at all times.
  • Old, deleted row versions are enevtually removed by VACUUM (or Autovacuum), the XID is no longer used.
  • Old row versions, which are still live, are marked as "freezed" in a table, and assigned a special XID - the previously used XID is no longer needed. The problem here is that every single table in every database must be Vacuumed before the 2 billion threshold is reached.
  • PostgreSQL uses lazy XIDs, where a "real" transaction id is only assigned if the transaction changes something on disk - if a transaction is read only, and does not change anything, no transaction id is consumed.

 

 

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How we manage the PostgreSQL FOSDEM devroom

The PostgreSQL Project was assigned a devroom at FOSDEM again this year. We got a room with approx. 200 seats, and as usual every last seat was taken for many of the talks. This requires that we manage the room very effectively and carefully, both to avoid that people walk in and out at all times and disturb the speaker, but also in order to keep the exits free at all times.

 

For a speaker it is quite disturbing if the door in the back opens, someone walks in, down all the way to the front, tries to find a seat, walk around to the other side, maybe leaves again, or just stays somewhere and blocks the exit. The worst case is when there is a free seat somewhere in the middle of a row, and everybody has to get up to let the new attendee in.

 

The FOSDEM team requires that we keep the exits free, in case the room needs to be evacuated. If people are staying on the steps along the wall, it is not possible to clear the room effectively and quickly.

 

 

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PostgreSQL @ FOSDEM 2018

For more than 10 years, the PostgreSQL Project is present at FOSDEM. We also organize a separate PostgreSQL Day on Friday.

This blog post presents useful information about both the PGDay and the booth and devroom at FOSDEM.

 

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PostgreSQL @ FOSDEM 2017 - Review

FOSDEM 2017 is over, and hopefully everyone is back home. Time for a short review.

Once again, PostgreSQL ran a pre-conference to FOSDEM, called PGDay. One day just filled with awesome PostgreSQL talks, and meeting community members.

Many speakers uploaded or linked their talks to the PostgreSQL Wiki. If the slides for a talk are missing, please contact the speaker and ask them to upload or link the slides. (For the record, my slides are here)

The FOSDEM video team already uploaded the recordings, and the PostgreSQL Volunteers reviewed every single video. Find them here. Devrim also did short recordings of most of the talks, and posted them on Twitter.

The Hacker Public Radio did interviews with many projects, including PostgreSQL. Find the interview here.

The PostgreSQL Project had a Devroom on Sunday. The schedule is part of the regular PGDay/FOSDEM schedule. And of course we managed to fill the room to the last seat, standing room only. If only people would obey the "Room is full" sign on the door ;-)

We also had a booth (pic 2, pic 3) in the main building, where you can talk with community members about anything around PostgreSQL. Also we had some nice merchandise. Matching the bad weather, the umbrellas went very well. We promise to have more next year.

Last but not least, Slonik visited FOSDEM. Here is just a short selection of pictures.

Hope to see you all next year!

 

P.S.: The next PostgreSQL Europe Conference will be in Warsaw, in October. Details can be found here.

Slides from my talk "Tour de Data Types: VARCHAR2 or CHAR(255)?" at FOSDEM 2017

I had the opportunity to talk about the many datatypes in PostgreSQL, in the PostgreSQL Devroom at FOSDEM 2017. It's quite interesting how many people only use the basic data types and don't know the broad range of types which PostgreSQL is offering.

My slides are available here: *click*

PostgreSQL @ FOSDEM 2017

Like the past 10 or so years, the PostgreSQL Project is present at FOSDEM 2017. We also organize a separate PostgreSQL Day on Friday.

This blog post presents vital information about both the PGDay and the booth and devroom at FOSDEM.

 

Continue reading "PostgreSQL @ FOSDEM 2017"

FOSDEM PGDay and Devroom 2016 - Announcement & Call for Papers

FOSDEM PGDay is a one day conference that will be held ahead of FOSDEM in Brussels, Belgium, on Jan 29th, 2016. This will be a one-day focused PostgreSQL event, with a single track of talks. Registration is required to attend, the registration will open soon. Since we have a limited number of seats available for this event, we urge everybody to register as soon as possible once open.

PostgreSQL Europe will also have our regular devroom at FOSDEM on Sunday the 31st, which will be held at the main FOSDEM venue at ULB. This day will, of course, continue to be free of charge and open to all FOSDEM entrants. No registration is required to attend this day.

For full details about the conference, venue and hotel, see http://fosdem2016.pgconf.eu/.


The call for papers is now open for both these events. We are looking for talks to fill both these days with content for both insiders and new users. Please see http://fosdem2016.pgconf.eu/callforpapers/ for details and submission information.

The deadline for submissions is December 7th, 2015, but we may as usual pre-approve some talks, so get your submissions in soon!


We will provide a special rate with the Brussels Marriott Hotel. For details, see http://fosdem2016.pgconf.eu/venue/.

FOSDEM PGDay and Devroom 2015 - Announcement & Call for Papers

FOSDEM PGDay is a one day conference that will be held ahead of FOSDEM in Brussels, Belgium, on Jan 30th, 2015. This will be a one-day focused PostgreSQL event, with a single track of talks. This conference day will be for-charge and cost 50€, and will be held at the Brussels Marriott Hotel. Registration is required to attend, the registration is open. Since we have a limited number of seats available for this event, we urge everybody to register as soon as possible once open.

PostgreSQL Europe will also have our regular devroom at FOSDEM on Saturday the 31st, which will be held at the main FOSDEM venue at ULB. This day will, of course, continue to be free of charge and open to all FOSDEM entrants. No registration is required to attend this day.

For full details about the conference, venue and hotel, see http://fosdem2015.pgconf.eu/.


The call for papers is now open for both these events. We are looking for talks to fill both these days with content for both insiders and new users. Please see http://fosdem2015.pgconf.eu/callforpapers/ for details and submission information.

The deadline for submissions is November 24th, 2014, but we may as usual pre-approve some talks, so get your submissions in soon!


We also have negotiated rate with the Brussels Marriott Hotel. For details, see http://fosdem2015.pgconf.eu/venue/.

FOSDEM PGDay and Devroom 2014 - Announcement & Call for Papers

FOSDEM PGDay is a one day conference that will be held ahead of FOSDEM in Brussels, Belgium, on Jan 31st, 2014. This will be a one-day focused PostgreSQL event, with a single track of talks. This conference day will be for-charge and cost 50€, and will be held at the Radisson Blu Royal Hotel in downtown Brussels. Registration is required to attend. Registration is not yet open, but will be soon. Since we have a limited number of seats available for this event, we urge everybody to register as soon as possible once open.

PostgreSQL Europe will also have our regular devroom at FOSDEM on Saturday the 1st, which will be held at the main FOSDEM venue at ULB. This day will, of course, continue to be free of charge and open to all FOSDEM entrants. No registration is required to attend this day.

For full details about the conference, venue and hotel, see http://fosdem2014.pgconf.eu/.


The call for papers is now open for both these events. We are looking for talks to fill both these days with content for both insiders and new users. Please see http://fosdem2014.pgconf.eu/callforpapers/ for details  and submission information.

The deadline for submissions is December 15th, 2013, but we may as usual pre-approve some talks, so get your submissions in soon!


We also have negotiated rate with the Radisson Blu hotel in Brussels. For details, see http://fosdem2013.pgconf.eu/venue/.

FOSDEM 2012 - PostgreSQL Devroom: Call for Speakers

The PostgreSQL project will have a Devroom at FOSDEM 2012, which takes place on February 4-5 in Brussels, Belgium. The Devroom will mainly cover topics for PostgreSQL users, developers and contributors. For more information about the event itself, please see the website at http://www.fosdem.org/2012/.


We are now accepting proposals for talks. Please note that we only accept talks in English.

Each session will last 45 minutes (including discussion), and may be on any topic related to PostgreSQL. Suggested topic areas include:

  • Developing applications for PostgreSQL
  • Administering large scale PostgreSQL installations
  • Case studies and/or success stories of PostgreSQL deployments
  • PostgreSQL tools and utilities
  • PostgreSQL hacking
  • Community & user groups
  • Tuning the server
  • Migrating from other systems
  • Scaling/replication
  • Benchmarking & hardware
  • PostgreSQL related products


Of course, we're happy to receive proposals for talks on other PostgreSQL related topics as well.


Please use our conference website to submit your proposal:

https://www.postgresql.eu/events/callforpapers/fosdem2012/


The deadline for submissions is December 20th, 2011. The schedule will be published and speakers will be informed by the end of the year.


Please also note my email about hotel reservation:

http://archives.postgresql.org/pgeu-general/2011-11/msg00000.php


PostgreSQL@FOSDEM 2011

Yeah, FOSDEM is already a week ago, but I found no time to blog about the event. Anyway, here I go:

This years edition of FOSDEM was very successfull, especially for the PostgreSQL project. We got two tables in the main building, which gave us plenty of space to present the project and talk with visitors. In addition, we had our devroom in the main building too. So, thank you to the FOSDEM team for this smart move.

The devroom had many visitors for all talks. We managed to have 6 talks, three very technical and three more user orientated.

I came with a car full of stuff to Brussels, and leaved on Sunday with just two boxes. We gave away all stressballs and all pens, and sold all elephants (again) and mugs. Only one or two bags from PGDay.EU 2010 are left and several shirts. Time to order new merchandising stuff ;-) The Perl table next to us brought a very large camel, obviously an eye-catcher.

This year I also found time to visit other interesting talks, and managed to meet good friends again. As every year, it was a very good event, just a bit cold outside ;-)