In reply to Tobias at Home: I would say it is different in many ways.
For example:
1. It's indoor, on plastic. Very different to rock.
2. You are in front of 500+ people.
3. You may have to climb several routes in relative quick succession (qualifying, semis, final, possibly super final). Maybe over 2 days.
4. You have one go on one route. There is no falling off and then just trying the route next door (like you could outside).
5. You may well have travelled half way across the globe just a few hours before.
And if you are Adam Ondra, you have probably entered the bouldering comp the following day, and a few days previously ticked 4 F8c's or something.
Full respect to anyone competing at a high level. Insanely difficult.