Good. To sum up this section, let's find out about one more operator:
ANY. Take a look:
WHERE price < ANY (
WHERE mountain_id = 1
In the above example, we want to find trips to the cities which are cheaper than any hiking trip to the mountain with id 1 (Mont Blanc, just to let you know). There are two hiking trips to Mont Blanc: one which costs 1000 and one which costs 300. If we find a city trip which is cheaper than any of these values, we show it in the result.
Again, other logical operators are possible: