mysql - Multiple aggregations in a single SQL statement -


i have sql table following structure:

id | datetime | value ---------------------

what results following structure:

id | value_avg_overall | value_avg_last_month | value_avg_last_week -------------------------------------------------------------------

currently using join, constructing query similar one:

select * (     select_overall inner join select_last_month on select_overall.id = select_last_month.id     ) inner join select_last_week on select_last_week.id = select_last_month.id;

i have simplified query make more readable, select_* statements simple select statements using group by avg() respective time ranges.

is effective way perform multiple aggregations , return of them in single result set in mysql?

this called conditional aggregation:

select    id,    avg(value) value_avg_overall,   avg(case when datetime > date_sub(curdate(), interval 1 month) value end)     value_avg_last_month,   avg(case when datetime > date_sub(curdate(), interval 1 week) value end)     value_avg_last_week mytable group id;

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