An evening with Psycopg2

The next meetup at Brighton will be Friday 14th October at 19.30.

Daniele Varrazzo will kindly talk about the most popular PostgreSQL driver in the python universe.
Psycopg is the most used PostgreSQL driver for the Python programming language.

As a driver it stays at a relatively low level, allowing to use all the features offered by the database. Behind the scenes, it does its best to convert the rich Python data model into the likewise rich PostgreSQL data model:
we will take a look at the adaptation mechanism and how to customize it to add new data types or change the default behaviour.

We will also take a look at how psycopg allows Python to tap into the PostgreSQL publish/subscribe mechanism and how this can be used to build reactive and distributed applications.
The presentation's live stream will be available at this link

http://www.youtube.com/channel/UCgr5Iv9eJYN2Piy9oYkn6jw/live

Please RSVP here.

See you in Brighton!

News from the outer ring

After the summer break the Brighton PostgreSQL meetup restarts with the monthly technical talks.

This time is my round again. I'll speak on how to scale the backup and recovery on large postgres installations.


Actually this is the talk I've submitted to the european pgconf.
I made the talk in a storytelling form in order to avoid to bore the audience to the death. The talk should be  quite entertaining with explanation of  the issues solved  by the DBA over the years.

As google is removing the hangouts on air I'm using youtube live and OBS to stream this event. It's the first time I try and I cannot guarantee it will work.

I'll record the presentation just in case the stream is broken.

Event details

PostgreSQL - backup and recovery with large databases

 

Friday 9th September 19.00 London Time Zone

Location: Brandwatch - 1st Floor Sovereign House, Church St, Brighton, East Sussex BN1 1UJ, Brighton

Description:
Dealing with large databases is always a challenge.
The backups and the HA procedures evolve meanwhile the database installation grow up over the time.
The talk will cover the problems solved by the DBA in four years of working with large databases, which size increased from 1.7 TB single cluster, up to 40 TB in a multi shard environment.
The talk will cover either the disaster recovery with pg_dump and the high availability with the log shipping/streaming replication.
The presentation is based on a real story. The names are changed in order to protect the innocents.

RSVP here

Live stream (hopefully) here

Meetup wrap up

This second meetup went very well. The audience was interested and we had fun time thanks to the beer and pizzas offered alongside with the venue by our sponsor brandwatch.

Here a couple of pictures from the meetup.

The recording worked much better than the previous time, here's the presentation's video. We'll meet again shortly for a nice beer. Next technical talk will be probably in January.

Streaming replication at the brighton postgresql meetup

November 27th at 19.00 GMT I'll talk at the Brighton PostgreSQL meetup.

This time the group chosen the streaming replication as topic.

The talk will cover the PostgreSQL write ahead logging and the crash recovery process. The audience will learn how to setup a standby server using the streaming replication and how to troubleshoot it.

Please RSVP here.

The next meetup - PostgreSQL query planning

Like previously said, the next Brighton PostgreSQL meetup will be September 25th at 7 pm BST. The topic chosen by the member is the query planning and execution in PostgreSQL.
I will do the presentation exploring the various steps a query passes through from the client to the execution. I'll also explain how to read the execution plan and why sometimes the executor seems to ignore the indices put in place for speeding up the operations.

The meetup is hosted kindly by Brandwatch

There are limited places so you want to join us secure your seat here

The sea elephants

Friday 14th August we kicked off the Brighton PostgreSQL  Meetup.
We had a nice evening with cool people all togheter discussing about PostgreSQL and how we can run effectively the meetup.

We decided to have a regular monthly meetup hosted around Brighton, possibly, by companies or any suitable venue.

The next meetup will be the 25th of September and this time there will be some PostgreSQL talks. The general interest favours the standby servers and the streaming replication. Another topic could be the query planning and execution.
I can cover both of the topics. We just need to decide how many talks will be in one hour session.

After the meetup we’ll head to the nearest pub for a nice beer.

I can only say a big thank you, to all the meetup members.

That’s all for now.  

Meet Marvin

There is just one day left and we'll start the Brighton PostgreSQL Meetup. I invested some resources in this project like and I truly believe it can be a success.
I still can't believe that in just one month 25 people already have shown  the interest on being part of the Brighton PostgreSQL Group. And today another nice suprise. I received the new shiny mascot for our group.

He's Marvin, the sea elephant. The author if this fantastic drawing is Elena, an incredibly talentuous artist from Italy. 

I've also opened a twitter account for our social media presence.

So we are ready to start. I'm very excited and I'll write a detailed report of our first meetup in few days.

Brighton PostgreSQL Meetup

After a while I finally started a PostgreSQL Meetup in Brighton.
I reckon there are several people interested in PostgreSQL in the UK and I've met many of them in the Sussex area.

I'm quite new to the Meetup platform so I still need to learn how to use it correctly. However, anybody is absolutely welcome to help to organise a PostgreSQL community in the area.

The link is here. http://www.meetup.com/Brighton-PostgreSQL-Meetup/
I've already scheduled a PostgreSQL beer, an informal chit chat about our database of choice and the future of the community.

Save the date,
Friday, August 14, 2015 6:30 PM.

 

The location is the Brunswick in Hove. Big beer garden, no music outside and nice ales.

 

Pythons elephants and zombie

Sorry for the delay.
I want to thank the brighton and hove python users group for the great evening.

As I promised here's the view to get the dead files on the PGDATA.
Dead files are files not mapped in the pg_class system table.
They can be present if any new file generation is interrupted by a crash recovery where the wal replay rollback the system catalogue operation but not delete the new files.
Not sure if this is a bug.
Anyway this is the code on pastebin.

Please be aware the view is specific for PostgreSQL 9.2. I'll try to build a self adapting version sooner or later.

http://pastebin.com/THzti7gW

As I had some interest in PostgreSQL I've started a simple google group, the sea elephants, for aggregating PostgreSQL users in the Brighton and Hove area.

I know there's a national usergroup (or some sort of it) but in my humble experience, local is better.

Because it's better to start from the little things, like a good beer in a lovely pub.

And yes this is an hint for the first meeting ever.