I love documentaries. I try to record as many as I can for those rainy / sick days. But selecting them all manually would be a tedious task. Thats why I use a custom recording rule in MythTV. This is the code I use:
(program.description LIKE '%Dokumentation%' OR program.description LIKE '%Dokumentarfilm%') AND (channel.callsign LIKE '3sat' OR channel.callsign LIKE 'arte') AND program.description NOT LIKE '%Eisenbahn%' AND program.description NOT LIKE '%kulinarisch%' AND program.description NOT LIKE '%Nachbarn%' AND program.title NOT LIKE '%Eurovision%' AND program.title NOT LIKE '%Gleis%' AND program.description NOT LIKE '%Tierdokumentation%'
The first parenthesis matches the description of all shows for the words that fairly often pinpoint to a documentation. The second parenthesis define the channels I know feature good documentaries. Lastly, after the parenthesis I define all the words that definitely point to something I do not want to record.