The 20th of April I was supposed to give the pgchameleon’s talk at the Pycon 9. However personal issues prevented me to come to Florence. This post is an explanation and an apology for the pycon 9 attendees and organisers.
Database administrators usually work behind the scenes, over the weekends and in antisocial hours. They strive to look after the database which is at the core of any business with little or no recognition.
The sad truth is that the DBA is one of the most obscure and one of the less appreciated roles within the IT organisations.
One of the things that distinguish PostgreSQL from other database systems is the way the dependencies between database objects are managed.
PostgreSQL do not allow any invalid object like views or functions. Therefore any action that can invalidate dependent objects results in an error or it’s propagated to the dependent objects.
The mechanism could be confusing at first sight. However the implementation is brilliant and gives great flexibility.
Before the release of pg_chameleon 2.0 I had to write an upgrade procedure to allow a smooth migration from the version 1.8.
An interesting challenge I faced was to determine the maximum and minimum position for the MySQL’s binary logs belonging to the same server but stored with different values in multiple sources.
The user defined aggregates, a feature pretty unique to PostgreSQL, allowed me to solve the problem in a robust and simple way.