Question

I have table A, table B and table C.

I want to select 2 fields from table A, one field from table B (an inner join between these two I’m assuming) and the Count for each record where the identifier on table B is found on table C.

So I’ll have:

OpeartiveId | OperativeNumber | JobLocation | CountOfJobIdInWorkTable

Edit:

Operative
OperativeId
OperativeNumber

Jobs
JobId
JobLocation

Work
JobId
OperativeId

Answer 1

Assuming you also want records from a and b that have no matching records in c, you’ll need an outer join:

select a.pk_a, b.pk_b, count(c.pk_c) 
from a 
inner join b on a.pk_a = b.pk_a 
left outer join c on b.pk_b = c.pk_b 
group by a.pk_a, b.pk_b;