-- { echo } select exists(select 1); select exists(select 1 except select 1); select exists(select number from numbers(10) where number > 0); select exists(select number from numbers(10) where number < 0); select count() from numbers(10) where exists(select 1 except select 1); select count() from numbers(10) where exists(select 1 intersect select 1); select count() from numbers(10) where exists(select number from numbers(10) where number > 8); select count() from numbers(10) where exists(select number from numbers(10) where number > 9);