如何计算BigQuery中列的布尔聚合？

Question

I have a table of events of users, and I want to project those events into a new column with some predicate, and then aggregate the events together per user into a new projection that tells me if a user has ever had the predicate match for them, or if they've never had it match, etc.

In other languages this is usually called all() and any() , where you pass it a list of boolean values and it will tell you if all of them match, or if at least one matches. It's equivalent to using a boolean AND on all boolean values (such as in the case with all ) or using a boolean OR on all boolean values (as in any ).

Does BigQuery have this feature? I can sort of approximate it using max and min but it's not ideal.

Example:

select
month(date_time) m,
count(*) as ct,
max(id_is_present),
min(id_is_present),
max(starts_with_one) max_one,
min(starts_with_one) min_one,
from
(
    select
    length(user_id) > 1 id_is_present,
    regexp_match(user_id, r'^1') starts_with_one,
    date_time
    from
    [user_events.2015_02]
)
group by
m

It's exploiting a behavior of max(true, false, false) yielding true , so you could sort of implement any and all by searching through the column for values and then building from there.

Is this the hack I have to rely on or does BigQuery support boolean aggregates?

Answer 1

Yes, BigQuery has such aggregation functions, it uses SQL Standard names for them:

EVERY (will do logical and)
SOME (will do logical or)

Answer 2

In case someone else stumbles across this, standard SQL offers logical_and() and logical_or . So, the code could be written as:

select month(date_time) as m, count(*) as ct,
       logical_or(id_is_present),
       logical_and(id_is_present),
       logical_or(starts_with_one) as max_one,
       logical_and(starts_with_one) min_one,
from (select length(user_id) > 1 id_is_present,
             regexp_match(user_id, r'^1') starts_with_one,
             date_time
      from [user_events.2015_02]
      ) u
group by m;