Wie bekomme ich min, median und max aus meiner Abfrage in postgresql
Ich habe eine Abfrage geschrieben, in der eine Spalte einen Monat enthält. Daraus muss ich den minimalen Monat, den maximalen Monat und den mittleren Monat ableiten. Unten ist meine Frage.
select ext.employee,
pl.fromdate,
ext.FULL_INC as full_inc,
prevExt.FULL_INC as prevInc,
(extract(year from age (pl.fromdate))*12 +extract(month from age (pl.fromdate))) as month,
case
when prevExt.FULL_INC is not null then (ext.FULL_INC -coalesce(prevExt.FULL_INC,0))
else 0
end as difference,
(case when prevExt.FULL_INC is not null then (ext.FULL_INC - prevExt.FULL_INC) / prevExt.FULL_INC*100 else 0 end) as percent
from pl_payroll pl
inner join pl_extpayfile ext
on pl.cid = ext.payrollid
and ext.FULL_INC is not null
left outer join pl_extpayfile prevExt
on prevExt.employee = ext.employee
and prevExt.cid = (select max (cid) from pl_extpayfile
where employee = prevExt.employee
and payrollid = (
select max(p.cid)
from pl_extpayfile,
pl_payroll p
where p.cid = payrollid
and pl_extpayfile.employee = prevExt.employee
and p.fromdate < pl.fromdate
))
and coalesce(prevExt.FULL_INC, 0) > 0
where ext.employee = 17
and (exists (
select employee
from pl_extpayfile preext
where preext.employee = ext.employee
and preext.FULL_INC <> ext.FULL_INC
and payrollid in (
select cid
from pl_payroll
where cid = (
select max(p.cid)
from pl_extpayfile,
pl_payroll p
where p.cid = payrollid
and pl_extpayfile.employee = preext.employee
and p.fromdate < pl.fromdate
)
)
)
or not exists (
select employee
from pl_extpayfile fext,
pl_payroll p
where fext.employee = ext.employee
and p.cid = fext.payrollid
and p.fromdate < pl.fromdate
and fext.FULL_INC > 0
)
)
order by employee,
ext.payrollid desc
Wenn es nicht möglich ist, ist es möglich, den maximalen Monat und den minimalen Monat zu erhalten.