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我正在尝试在 mongodb 中编写 hyperloglog。mongodb中查询的等效版本(用oracle编写)是什么

create table my_hll as
select mod(ora_hash(n), 1024) bucket,
max(num_zeroes(trunc(ora_hash(n)/1024)))+1 val
from previous_data
group by mod(ora_hash(n), 1024);
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