Justin wrote:
yes. The question is why are the to sides not equal anymore
Take this
Select
'2',
round(sum( beginBalance ),6) as beginbalance,
round(sum( negative ),6) as debit,
round(sum( positive ),6) as credit,
round(sum( difference ),6) as difference,
round(sum( endbalance),6) as endbalance
from trailbalance
union
Select
'1',
sum( round(beginBalance,6)) as beginbalance,
sum( round(negative,6)) as debit,
sum( round(positive,6)) as credit,
sum( round(difference,6)) as difference,
sum( round(endbalance,6)) as endbalance
from trailbalance
"1" -0.000006 -11250546.743752 11250546.743752 0.000000
-0.000007
"2" 0.000000 -11250546.743752 11250546.743752 0.000000
0.000000
At the very least this show a clear warning when rounding do it after
all the sum function is called not before.
IFAIK (dimly recalling numerical analysis courses at university) SUM and
ROUND can *never* be commuted. In general the recommended approach is to
round as late as possible and as few times are possible - so your 1st
query is the correct or best way to go.
Cheers
Mark
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
