As you might know, Akonadi uses a relational database system for storing meta information about the PIM data it manages. Since the first official release this has been MySQL because it provided all features we needed and was shipped with every modern Linux distribution. However there have always been users complaining about the usage of MySQL. They claim it is big, slow and has not the right license.... Leaving the FUD away, it can never be wrong to support multiple database systems, so during the last months we got several contributions from the community that allowed Akonadi to use PostgreSQL as its database. Unfortunately the patches only allowed to make use of an already running and properly configured server, which is something you can't expect from a user who just wants to read emails or looking up something in the address book.
So yesterday I took a couple of hours and checked whether it is possible to implement PostgreSQL support like it is done for MySQL, namely that Akonadi starts its own instance of the database server with a custom data directory and connects to it via unix domain sockets, so every user can have its own database server running. At the end of the day I had a working solution and after crosschecking with other PIM developers that my changes won't break anything I committed the patch this morning to trunk. If you want to test it, simply rebuild the Akonadi server from trunk, cleanup your Akonadi installation and configuration and change the content of $HOME/.config/akonadi/akonadiserverrc to
[%General]
Driver=QPSQL
[QPSQL]
StartServer=true
Now after a restart PostgreSQL should be used instead of MySQL. At this point I'd like to ask you, dear reader, for some help. The code that searches for the postgres executable has some paths predefined where the executable could be located. Unfortunately that differs from distribution to distribution. So can you tell me in the comments where the executable can be found in your distribution, please? Under Debian it is /usr/lib/postgresql/8.4/bin/, where is it under SuSE or Fedora?
Thanks for your help!