Hello,

First, that means that something went wrong at one moment :
- previous update (Joomla sql updater failled at this moment)
- Multiple install/uninstall of different versions, and with manifest iCagenda version refreshed by error (cache reset).

So, the first thing to do is to check if not any other columns is wrong (missing, or not with correct type).

Go to your PhpAdmin board, and compare iCagenda tables with the fresh install sql request of the latest iCagenda version( you will find this file here : /admin/sql/install/mysql/icagenda.install.sql

Then, tell me if any columns missing (else than the 'slug').
And check for all tables of course! (in case one table was missing).

Waiting for your control feedback

Note: do you remind from which older version you have updated ?
Note2: no need of a sql request, you can add the columns in place directly using PhpAdmin

Best regards,
Cyril