Hi. Quarry newbie here, thought I'd try the Empty categories example. It comes back with 46564 rows which is obviously wrong, looking more closely it tries to knock out anything in the category "Wikipedia category redirects" which was deleted last year. I wouldn't want to edit the example myself for fear of doing something stooped, but I assume it needs to be replaced with "Wikipedia soft redirected categories". Hmm - I've just tried that, and it comes back with a similar number of rows and includes categories like which is a category redirect. Some of the standard database reports over on en:wiki have started having problems with this in recent weeks, I don't know if something has changed in the underlying database which means that it's not seeing categories in templates all of a sudden?!?
Topic on Talk:Quarry/Flow
In quarry:query/7554, you wrote Wikipedia soft redirected categories, but the database uses underscore instead of space in category names, so you must use Wikipedia_soft_redirected_categories instead. Since you used spaces instead of underscores in your query, the result set includes category redirects.
Doh! It's been too long since I've done much of this kind of stuff. Although that now creates a new problem. The original example code (and my first try with Wikipedia soft redirected categories) took 20-25 minutes to run, I've now tried three times and with underscores it takes it over the 30-minute kill limit. Suggestions? (or does someone have the power to give me a bit more than 30 minutes? <g>)