Good day,
I have a table with biometric info about employees (let's call it bioemployee):
id serial not null -- primary key
employee_id -- foreign key references employee table
day char(8) -- YY-MM-DD
sign_in TIMESTAMP
total_hours INTEGER
I want to display details grouped by day & employee Id, for example:
Day Employee Total-Hours First-Sign-In Last-Sign-In
20/4 emp1 4 8:22 3:25
21/4 emp1 7 9:00 4:11
21/4 emp2 2 11:00 01:11
I created a pgsql function to get the details through the below query:
select employee_id, day, sum(total_hours) as total_hours, (select name from employee where id = employee_id) as emp_name
from bioemployee where sign_in BETWEEN X and Y GROUP BY employee_id, day ORDER BY day;
now the problem is with getting First-Sign-In & Last-Sign-In per group (employee & day), I have currently implemented it in a FOR loop:
for RECORD in query LOOP
--First-Sign-In
select sign_in from bioemployee where employee_id = -- and day = -- and sign_in BETWEEN X and Y ORDER BY sign_in LIMIT 1;
--Last-Sign-In
select sign_in from bioemployee where employee_id = -- and day = -- and sign_in BETWEEN X and Y ORDER BY sign_in DESC LIMIT 1;
return next json_build_object(first_sign_in, last_sign_in, ..rest of details);
END LOOP
but If I had 100 employees over a span of 30 days, this would be 6000 queries inside the loop! which I am sure you would agree is an overkill
is there a better way to do this?
Thanks.
