The idea is to get up there, not to just visit the basilica!
People from Bologna often do it as a promise, something like "If I pass the exam I'll walk up to San Luca", but from the number of people you can meet during the walk, you can guess there are not only promises to keep here but also fitness practise, weekly habits, picnics grouping and a lot of turism of course.
It's a 3.5 km walk, totally worthy! It's not too difficult, except for the last bit, where you find a lot of steps. Generally it's a long nice walk under an old (and not well ketp) covered path that you can take on a rainy day as well.
The view from the top of the hill is nice and there's a bar to get refreshed if you need. The church in itself is small but pretty and you can visit behind the main altar, when it's open.
Compare to the way up, the way down takes few minutes!
You can of course drive up the church as well, if you can't walk that much. I think there's a bus running as well, but I'm not 100% sure.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.