Hi,
I sum values of array integers by query
select sum(t)
from unnest(array[1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0]) as t
cross join generate_series(1, 1000000);
Total runtime: 10020.699 ms
But simmilar method to count array's elements is dramatically faster
select sum(array_length(array[1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0], 1))
from generate_series(1, 1000000)
Total runtime: 464.042 ms
It's as fast as simple query!
select sum(1) from generate_series(1, 1000000)
"Total runtime: 462.687 ms"
It is possible that function e.g. array_sum written in C is as fast as
bult-in array_length?
regards
Wojciech
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