Count function in select subquery

Question

I'm trying to solve the query below, but can't get it to work completely so really need some help. What I'm trying to get as a result is the following:

Part that is working

• The personnel number stored as foreign key in the hrs_hours table
• The full name stored in the prs_personel table
• The sum of all normal hours in seconds from the hrs_hours table
• The sum of all ort (special) hours in seconds from the hrs_hours table

Part that is not working

• The count of tasks where hrs_taskname = 'Partus Assistentie' and is performed on the weekend by a personnel member for an entire month in a specific year.
• The count of tasks where hrs_taskname = 'Partus Assistentie' and is performed on a weekday by a personnel member for an entire month in a specific year.

Results of query:

No rights to place an image, so hope the results are clear in this manner.

• hrs_prs_fkey (integer): 6 , 11
• prs_fullname (text): name 1, name 2
• normal_time (double precision): 46800, 461340
• ort_time (double precision): 29700, 116100
• partusass_weekend: 0, 0
• partusass_week: 2, 2

In the results you can see that the partusass_week is the total amount of those task in the month of a year. However they have both performed 1 of those task totaling the amount 2, and thus I would like them to display 1 and 1 instead of 2 and 2. How should I phrase my (select count ...etc... ) sub-queries in order to get the results that I would like?

SELECT hrs_prs_fkey, 
prs_fullname, 
SUM(EXTRACT (epoch FROM hrs_normaltime)) AS normal_time, 
SUM(EXTRACT (epoch FROM hrs_orttime)) AS ort_time, 

(SELECT Count(hrs_taskname) AS partusass_weekend FROM hrs_hours 
WHERE hrs_taskname = 'Partus Assistentie'
AND EXTRACT(MONTH FROM "hrs_date") = 7 
AND EXTRACT(YEAR FROM "hrs_date") = 2015
AND extract(dow from hrs_date) in (0,6)), 

(SELECT Count(hrs_taskname) AS partusass_week FROM hrs_hours 
WHERE hrs_taskname = 'Partus Assistentie' 
AND EXTRACT(MONTH FROM "hrs_date") = 7 
AND EXTRACT(YEAR FROM "hrs_date") = 2015
AND extract(dow from hrs_date) in (1,2,3,4,5))

FROM hrs_hours 
LEFT JOIN prs_personel ON hrs_hours.hrs_prs_fkey = prs_personel.prs_pkey 
WHERE EXTRACT(MONTH FROM "hrs_date") = 7 
AND EXTRACT(YEAR FROM "hrs_date") = 2015 
GROUP BY hrs_prs_fkey, prs_fullname 
ORDER BY hrs_prs_fkey ASC

Thank you in advance for reading and thinking along.

Answer 1

I think you just want conditional aggregation:

SELECT hrs_prs_fkey, prs_fullname, 
       SUM(EXTRACT(epoch FROM hrs_normaltime)) AS normal_time, 
       SUM(EXTRACT(epoch FROM hrs_orttime)) AS ort_time, 
       SUM(CASE WHEN hrs_taskname = 'Partus Assistentie' AND
                     extract(dow from hrs_date) in (0, 6)
                 THEN 1 ELSE 0 END
           END),
       SUM(CASE WHEN hrs_taskname = 'Partus Assistentie' AND
                     extract(dow from hrs_date) in (1, 2, 3, 4, 5)
                 THEN 1 ELSE 0 END
           END)
FROM hrs_hours LEFT JOIN
     prs_personel
     ON hrs_hours.hrs_prs_fkey = prs_personel.prs_pkey 
WHERE EXTRACT(MONTH FROM hrs_date) = 7 AND
      EXTRACT(YEAR FROM hrs_date) = 2015 AND
GROUP BY hrs_prs_fkey, prs_fullname 
ORDER BY hrs_prs_fkey ASC