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select
a,
first_value(a) over () f,
nth_value(a, 1) over () n1,
nth_value(a, 2) over () n2,
nth_value(a, 3) over () n3,
nth_value(a, 4) over () n4,
last_value(a) over () l
from (
select 1 a from dual union all
select 2 from dual union all
select 3 from dual union all
select 4 from dual
) t
order by a