We have a survey that needs db support for more than 2500 columns. The limesurvey docs mentions that with postgresql one can increase the blocksize to 16K or 32K to have more columns available. I wasn't able to find instructions on the net on how to do this. Can please someone direct me to some manuals or give me a hint on how to perform this? Thank you!

Best regards, Adrian Zaugg.

System: Debian lenny, postgresql 8.3, newest limesurvey

Well, that's a question you should better ask in a postgres forum.

No, I prefer to reply to myself:

You need to recompile postgresql and set BLCKSZ to a higher value, like 16kiB or 32kiB. In Debian one would do this approximately like this:

sudo apt-get build-dep postgresql-8.3
apt-get source postgresql-8.3
cd postgresql-8.3-*
debian/rules patch
sensible-editor build-tree/postgresql-8.3.5/src/include/pg_config_manual.h
dpkg-buildpackage -us -uc -b -nc

(Thanks to Martin Pitt)

It just remains the question why LimeSurvey needs that many columns. The database design of LimeSurvey seems to be strange in this regard.

Regards, Adrian.

Thanks for your feedback. Can you please add your solution to manual -> workarounds and add a link at the installation FAQ where the hint to increase block size is listed!?

Thanks a lot!

Limesurvey 2 will use a different database layout