Clicking 'Run' on the 6.min exercise of Aggregate Functions produces an eternal loading wheel. No amount of waiting, refreshing, re-entering, browser changing, cache clearing, or computer restarting allows me to proceed. I am pretty confident that the code I have entered is correct and that it is a problem with the interface:
SELECT name, category, MIN(downloads) FROM fake_apps
GROUP BY catgeory;
I had a similiar problem earlier on with a different exercise and checked the forums, discovering that leaving off the semi-colon at the end somehow allowed you to proceed. However, the semi-colon is absolutely essential in this exercise, so there is no such workaround.
Hopefully this will be resolved tomorrow.