How do you work out the average of a sum function within a temp table? - sql

Question

I have created a temp table that lists each client's invoice(s), plus the number of days it took to pay the invoice. A client can have more than one invoice.
Instead of this, I would just like the temp table to list each client once, along with the AVERAGE number of days it took to pay all of their invoices.
Any tips on how to do this would be much appreciated.
Thanks
select
c.client_code,
b.bill_num,
b.bill_date,
ba.TRAN_DATE,
sum(datediff(Day,b.BILL_DATE, ba.TRAN_DATE)) as Days_To_Pay
into #tempG1
from blt_bill b
left outer join blt_billm bm on b.tran_uno = bm.bill_tran_uno
left outer join BLT_BILL_AMT ba on bm.BILLM_UNO = ba.BILLM_UNO
left outer join hbm_matter m on bm.matter_uno = m.matter_uno
left outer join hbm_client c on m.client_uno = c.client_uno
where b.total_bill_amt > 0.0
and bm.ar_status NOT IN ('P','X')
and ba.TRAN_TYPE in ('CR','crx')
group by c.client_code,b.bill_num,b.bill_date,ba.TRAN_DATE
select * from #tempG1
Drop Table #tempG1

Answer 1

I am not familiar with temp tables, but this should work (tested on a simliar scenario on MySQL8 and assuming that #tempG1 return results):
select
c.client_code,
b.bill_num,
b.bill_date,
ba.TRAN_DATE,
sum(datediff(Day,b.BILL_DATE, ba.TRAN_DATE)) as Days_To_Pay
from blt_bill b
left outer join blt_billm bm on b.tran_uno = bm.bill_tran_uno
left outer join BLT_BILL_AMT ba on bm.BILLM_UNO = ba.BILLM_UNO
left outer join hbm_matter m on bm.matter_uno = m.matter_uno
left outer join hbm_client c on m.client_uno = c.client_uno
where b.total_bill_amt > 0.0
and bm.ar_status NOT IN ('P','X')
and ba.TRAN_TYPE in ('CR','crx')
group by c.client_code,b.bill_num,b.bill_date,ba.TRAN_DATE
into #tempG1
############################
SELECT temp.client_code, AVG(temp.Days_To_Pay)
FROM (select * from #tempG1) as temp
GROUP BY temp.client_code
############################
#### Do you see results if drop? ####
Drop Table #tempG1
Note that I put #tempG1, at the bottom of your SELECT request, but might not be what want to achieve, not sure if you want to include your JOIN conditions or not.
Or you could do without temp table(including your join conditions):
SELECT temp.client_code, AVG(temp.Days_To_Pay)
(
select
c.client_code,
b.bill_num,
b.bill_date,
ba.TRAN_DATE,
sum(datediff(Day,b.BILL_DATE, ba.TRAN_DATE)) as Days_To_Pay
from blt_bill b
left outer join blt_billm bm on b.tran_uno = bm.bill_tran_uno
left outer join BLT_BILL_AMT ba on bm.BILLM_UNO = ba.BILLM_UNO
left outer join hbm_matter m on bm.matter_uno = m.matter_uno
left outer join hbm_client c on m.client_uno = c.client_uno
where b.total_bill_amt > 0.0
and bm.ar_status NOT IN ('P','X')
and ba.TRAN_TYPE in ('CR','crx')
group by c.client_code,b.bill_num,b.bill_date,ba.TRAN_DATE
) as temp
GROUP BY temp.client_code

Answer 2

This sounds like a simple aggregation:
select c.client_code, avg(datediff(Day, b.BILL_DATE, ba.TRAN_DATE)) as Days_To_Pay
from blt_bill b join
blt_billm bm
on b.tran_uno = bm.bill_tran_uno join
BLT_BILL_AMT ba
on bm.BILLM_UNO = ba.BILLM_UNO join
hbm_matter m on bm.matter_uno = m.matter_uno join
hbm_client c
on m.client_uno = c.client_uno
where b.total_bill_amt > 0.0 and
bm.ar_status not in ('P', 'X') and
ba.TRAN_TYPE in ('CR', 'crx')
group by c.client_code;
Note that you do not need outer joins. The where clause is turning most of them into inner joins anyway. Plus, if you are aggregating by the client code, then presumably you want a non-NULL value.