Sum the count(*) of between three tables

Question

I want to sum the number of counts between 3 tables. I have added three input fields to give a specific date each time but I am struggling on how to SUM the COUNTS(*)

select count(*)
from db.table1
where call_date = ${var:call_date};

select count(*)
from db.table2
where call_date = ${var:call_date};

select count(*)
from  db.table3
where call_date= ${var:call_date};

thanks in advance

Answer 1

UNION ALL the selects. SUM() the result.

select sum(cnt) from
(
    select count(*) cnt
    from db.table1
    where call_date = ${var:call_date}
    UNION ALL
    select count(*)
    from db.table2
    where call_date = ${var:call_date}
    UNION ALL
    select count(*)
    from  db.table3
    where call_date= ${var:call_date}
) dt