Julius Stroffek's Weblog

Prague PostgreSQL Developers' Day 2008

Yesterday, Prague was hosting its first PostgreSQL developer conference. It was organized by the people around the Czech database portal - http://www.dbsvet.cz with support from companies CZ.Nic and Sun Microsystems. The conference was hosted by Czech Technical University, Faculty of Electrical Engineering. Peter Eisentraut, the PostgreSQL core team member was the guest of the conference.

At about 60 people interested in PostgreSQL from the both user and developer point of view attended the conference. A bunch of them were students from Faculty of Electrical Engineering or Faculty of Mathematics and Physics at Charles University.

The conference was followed by the unformal discussions at the pub in the evening as usual. We went to the pub where Peter was staying called "U Medvidku". Couple of guys here using PostGIS stressed the value of geographical data functionality that is offered by this extension and presented the opinion that this should become a part of the core distribution. However, this has some open issues, especially the licensing of PostGIS is GNU GPL and not BSD License as PostgreSQL. The idea was that it should not be much work to re-implement this from scratch as a contrib module. So there are no objections, start with a proposal and go ahead!

We all agreed that it was a great event and we all believe that we will meet again at the same conference next year.

I'll try to summarize the talks presented at the conference...

What's going on (PostgreSQL 8.3)
Peter Eisentraut

Peter presented an overview of new features introduced in new PostgreSQL version 8.3 released just a week before the conference.

Stored Procedures and SQL/PSM Language
Pavel Stehule

Pavel presented an overview of approaches to stored procedures/functions in different databases and ANSI SQL with a highlight to status in PostgreSQL. Pavel has done a lot work on support of different procedural languages in PostgreSQL and he is interested in SQL/PSM language support for PostgreSQL. He listed a couple of the features he would like to work on.

He was arguing against the standard three tier application architecture and introduced the idea of open database where all the functionality on the data is implemented on the database in stored procedures. The user then can access the data in the same way as the application does and do not need to rely on the proprietary communication protocol to the application server.

Personally, I liked the idea of the open database, however application server gives a bunch of other possibilities for the developers. You have a separated workload on the database and application server and scale each of these separately, you can also make your application portable across different database systems from simple embedded database like SQLite or JavaDB through MySQL to enterprise level databases like PostgreSQL or even proprietary databases like Oracle.

I think that it would be necessary to have a good standard of procedural language implemented among the various databases and have a bunch of libraries available to provide the functionality that is already available in different languages. Yes, of course I know you can implement stored procedures in whatever you like for PostgreSQL but then you are binding your application to PostgreSQL only and can not use an embedded database. The most likely, it's to late to achieve just the two tier application world.

PostgreSQL and XML
Peter Eisentraut

Peter presented a new XML functionality he was working on in a new version. He presented xml data type, storage, features for xml creation, XPath, XLabel and related features and possibilities to create a functional indexes on related functions. The current status of XML support contains just the basic functionality and has a lot of space for other features and improvements based and the feedback obtained from the users. So, feel free to provide your experience and suggestions.

Full-Text Search in PostgreSQL
Julius Stroffek

I gave a talk about the full text search feature in PostgreSQL. I presented related data types (tsvector, tsquery), operator, functions, ranking, database objects offered for full-text search (parsers, templates, dictionaries and configurations) and the way of how to provide your own full-text search configuration for the different language or tune the existing ones. Since there is no support for Czech language now in PostgreSQL, people were mostly interested in having the Czech dictionary for full-text search. I showed a way how to create a Czech dictionary from the ispell dictionary easily, however this approach has couple of issues especially with finding a root form for irregular words.

Data Integrity Checks in PostgreSQL
Robert Mach

Rober was working on analysis and algorithms for integrity checks for PostgreSQL as his thesis at Faculty of Electrical Engineering. He was talking about the functions a the way of how to deal with invalid blocks and/or checksums and possible repairs. There was a short discussion about the integration to PostgreSQL afterwards.

Robert just finished his final exams the day before the conference. Congratulations, Robert! ;-)

PostgreSQL on Solaris
Zdenek Kotala

Zdenek was talking about the integration of PostgreSQL to Solaris, problems that were caused during the integration of 8.1 into Solaris 10 U2. He presented Solaris features like ZFS, DTrace, RBAC that users can take an advantage of when using PostgreSQL on Solaris.

Query Processing in PostgreSQL
Tomas Kovarik

Tomas gave the overall overview of PostgreSQL architecture and the way how the queries are handled internally. He went through the parser, rewriter, trigger system, planner, join order optimization, handling of outer joins, executor, etc.

Registration Systems for .cz Domains and PostgreSQL
Jaromir Talir

Jaromir is working on the domain registration software for Czech domain registry. He was explaining the architecture of the project and the way they are using PostgreSQL as a database backend. He explained couple of problems they were dealing with the database. They started to develop the project two years ago and their system is running in production for about half a year now. They had to move the data from Informix database to PostgreSQL during the migration.

Posted at 02:22PM Feb 14, 2008 by julo in Sun  |  Comments[2]