SQL subquery in query

Question

I have a table with payment:

worker_id, amount, payed, date

Table workers:

id, name, lname

I need to write SQL that will give me name, lname and sum for jun, july, august, september.

Name | Lname | Sum_JUN | Sum_JULY | Sum_AUG | Sum_SEP

I'm trying with subqueries but can't do it. Can you help me?

I created SQL (example). I will replace dates in PHP.

select w.name, w.lname,
sum(case when p.payed_date between '2014-06-01' and '2014-06-31' then p.amount else 0 end) `sum_june`,
sum(case when p.payed_date between '2014-07-01' and '2014-07-31' then p.amount else 0 end) `sum_july`,
sum(case when p.payed_date between '2014-08-01' and '2014-08-31' then p.amount else 0 end) `sum_august`,
sum(case when p.payed_date between '2014-09-01' and '2014-09-31' then p.amount else 0 end) `sum_september`,
sum(case when p.payed_date between '2014-10-01' and '2014-10-31' then p.amount else 0 end) `sum_november`
from worker w
left join worker_sum p on(w.id = p.worker_id)
group by w.id

Answer 1

You can use conditional aggregation for your desired sum,But this will give you the sum for months from all years exist in your table

select w.*,
sum(case when month(p.date) = 6 then p.amount else 0 end) `sum_june`,
sum(case when month(p.date) = 7 then p.amount else 0 end) `sum_july`,
sum(case when month(p.date) = 8 then p.amount else 0 end) `sum_august`,
sum(case when month(p.date) = 9 then p.amount else 0 end) `sum_september`
from workers w
left join payment p on(w.id = p.worker_id)
group by w.id