combining queries runs longer - sql

Question

I have 2 queries. Individually, both run well. How when I combine them, they run terribly slow and time out on me. The second query is returning a list of invoices that I want to use in the IN clause in the first query. Not sure if I'm doing something wrong. Thanks for your help....
select
ba.bill_acct_nbr,
ba.acct_name,
i.inv_id,
i.prnt_tmsp,
i.due_dt,
d.dvr_frst_name,
d.dvr_srnm,
r.ecr_ticket_no,
r.co_tmsp,
i.dr_note_amt ,
ht.amt HT,
vat.amt VAT
from rfs.rnt_agr_inv_notes i
inner join rfs.rnt_Agrs r on r.rnt_agr_nbr = i.rea_rnt_agr_nbr
inner join rfs_rv.dvr_rras d on r.rnt_agr_nbr = d.rdy_rnt_agr_nbr and d.main_dvr_flg = 'MR'
inner join rfs_rv.bus_acnts ba on ba.acct_id = i.bac_acc_id
inner join (select sum(chg_amt) amt, rain.inv_id
from rfs.rra_chgs rrc
inner join rfs.rnt_agr_inv_note_lns rainl on rrc.rrc_id=rainl.rrc_rrc_id
inner join rfs.rnt_agr_inv_notes rain on rainl.rai_inv_id=rain.inv_id
inner join rfs.rnt_agrs ra on rain.rea_rnt_agr_nbr=ra.rnt_agr_nbr
inner join rfs.rra_chg_typs rct on rrc.rct_chg_typ=rct.chg_typ
where rrc.rct_chg_typ not in ('TAX', 'SUR', 'VAT') and not ( ra.stn_system='ECR' and (rrc.rct_chg_typ ='02000' or rrc.rct_chg_typ ='02201'))
group by rain.inv_id) ht on ht.inv_id=i.inv_id
inner join (select sum(chg_amt) amt, rain.inv_id
from rfs.rra_chgs rrc
inner join rfs.rnt_agr_inv_note_lns rainl on rrc.rrc_id=rainl.rrc_rrc_id
inner join rfs.rnt_agr_inv_notes rain on rainl.rai_inv_id=rain.inv_id
inner join rfs.rnt_agrs ra on rain.rea_rnt_agr_nbr=ra.rnt_agr_nbr
inner join rfs.rra_chg_typs rct on rrc.rct_chg_typ=rct.chg_typ and not ( ra.stn_system='ECR' and rrc.rct_chg_typ ='02200')
where rrc.rct_chg_typ in ('TAX', 'SUR', 'VAT')
group by rain.inv_id) vat on vat.inv_id=i.inv_id
where
i.inv_id in (425001975206,550008226812,425002005105, 425002046396, 42500190929)
I commented out the last line above and replaced it with this code; which runs well by itself.
i.inv_id in (select
q.inv_id
from
rfs.rnt_agr_inv_notes q,
rfs_rv.bus_acnts ba
where
ba.acct_id = q.bac_acc_id
and ba.bill_acct_nbr IN ('16785616')
AND extract(MONTH from q.prnt_tmsp) = 5
AND extract(YEAR from q.prnt_tmsp) = 2015)

Answer 1

I can give you a solution for combining the two which has worked well for our product. It looks horrible but had a vastly huge performance improvement by generating the list of Ids up front in a temp table.
(As an aside, you really need to take a look at the huge amount of INNER JOIN in your query as this is not helping your performance).
You'd want something like this:
CREATE TABLE #invIds (id INT)
INSERT INTO #invIds (id) SELECT
q.inv_id
from
rfs.rnt_agr_inv_notes q,
rfs_rv.bus_acnts ba
where
ba.acct_id = q.bac_acc_id
and ba.bill_acct_nbr IN ('16785616')
AND extract(MONTH from q.prnt_tmsp) = 5
AND extract(YEAR from q.prnt_tmsp) = 2015
Then the query would do this
d.dvr_frst_name,
d.dvr_srnm,
r.ecr_ticket_no,
r.co_tmsp,
i.dr_note_amt ,
ht.amt HT,
vat.amt VAT
from rfs.rnt_agr_inv_notes I .....
.....where
i.inv_id in #invIds