Introduction to Hacking PostgreSQL

Gavin Sherry and I have presented several versions of a tutorial introduction on how to modify the PostgreSQL source code. The original version was given at the PostgreSQL Anniversary Summit in June of 2006. Gavin has since given a revised version of the talk (at LCA 2007), as have I (at PgCon 2007).

All three versions of the talk follow a similar format: the first 90 minutes provid a general introduction to the backend, common coding conventions, and the procedure that is typically followed for submitting a new patch. The second 90 minutes walk the audience through an example patch.

Ottawa (PgCon 2007)

• Presentation slides
• Handout with excerpts from patch
• Complete example patch implementing the TABLESAMPLE clause (context diff against the CVS HEAD code as of May 19, 2007)
• Excerpts from the SQL standard for the TABLESAMPLE clause

Australia (LCA 2007)

Gavin presented an updated version of this tutorial at the PostgreSQL mini-conf that preceded LCA 2007. The slides and handouts for that talk are available.

Toronto (Anniversary Summit, 2006)

• Presentation Slides
• An example patch that adds support for the WHEN clause to the CREATE TRIGGER statement
• Handout of notable sections of code from the example patch; when the slides include statement like "see page n", they are referring to pages from this handout

Other Talks

I've given two other talks on PostgreSQL internals:

• "Inside the PostgreSQL Query Optimizer" describes how the optimizer works (as of April 2005). It is slightly out of date with respect to a few details, but is still mostly accurate.
• "Query Evaluation Techniques in PostgreSQL" discusses the algorithms for implementing scans, joins, and aggregation used in PostgreSQL (as of October 2007).

Tom Lane gave a great talk on "recent" improvements to the PostgreSQL query optimizer in 2003. Despite being slightly dated, it is still worth reading.

Changelog

• October 31, 2007: Added links to other talks on Postgres internals, added some new content to the Ottawa slides.
• May 21, 2007: Added Ottawa version of the talk.
• May 9, 2007: Linked to Gavin's modified LCA talk.
• July 11, 2006: Initial version posted.
• July 21, 2006: Made various minor corrections to the slides. Added email addresses for Gavin and myself.