Hello,



I am running DB2 v7.2 on NT.



suppose I ussue following simple SQL stmt:



select

3/18*18,

dec(3,8,3)/dec(18,8,3)*dec(18,8,3),

dec(3,31,8)/dec(18,31,8)*dec(18,31,8),

dec(3,30,8)/dec(18,30,8)*dec(18,30,8)

from sysibm.sysdummy1



The results are





3



1.8



Why doesn't the dec(..,31,8) give the correct result ?

Can anyone explain this ?

30,8 works. 29,8 works, ........





Thanks in advance





Peter


--
Posted via http://dbforums.com

That worked exactly as designed.
Please see "SQL Reference, Chapter 2. Language elements, Expressions
with arithmetic operatiors"

SELECT *
FROM (VALUES
('1. Operands', 'Integer', 'DEC(8,3)', 'DEC(31,8)',
'DEC(30,8)')
, ('31. Result'
, CHAR(3/18*18)
, CHAR(dec(3, 8,3)/dec(18, 8,3)*dec(18, 8,3))
, CHAR(dec(3,31,8)/dec(18,31,8)*dec(18,31,8))
, CHAR(dec(3,30,8)/dec(18,30,8)*dec(18,30,8))
)
, ('21. Mid Result'
, CHAR(3/18)
, CHAR(dec(3, 8,3)/dec(18, 8,3))
, CHAR(dec(3,31,8)/dec(18,31,8))
, CHAR(dec(3,30,8)/dec(18,30,8))
)
, ('20. DEC(p,s)/DEC(p'',s'') -> DEC(31 , 31-p-s+s'')'
, 'Large integer'
, '(8,3)/(8,3)->DEC(31,23)'
, '(31,8)/(31,8)->DEC(31,0)'
, '(30,8)/(30,8)->DEC(31,1)'
)
, ('30. DEC(p,s)*DEC(p'',s'') -> DEC(min(31,p+p'') ,
min(31,s+s''))'
, 'Large integer'
, '(31,23)*(8,3)->DEC(31,26)'
, '(31,0)*(31,8)->DEC(31,8)'
, '(31,1)*(30,8)->DEC(31,9)'
)
) AS t
ORDER BY 1
;
---------------------------------------------------

1 2
3 4
5
-----------------------------------------------------------
------------- ---------------------------------
--------------------------------- ---------------------------------
1. Operands Integer
DEC(8,3) DEC(31,8)
DEC(30,8)
20. DEC(p,s)/DEC(p',s') -> DEC(31 , 31-p-s+s') Large
integer (8,3)/(8,3)->DEC(31,23) (31,8)/(31,8)->DEC(31,0)
(30,8)/(30,8)->DEC(31,1)
21. Mid Result 0
00000000.16666666666666666666666 0000000000000000000000000000000.
000000000000000000000000000000.1
30. DEC(p,s)*DEC(p',s') -> DEC(min(31,p+p') , min(31,s+s')) Large
integer (31,23)*(8,3)->DEC(31,26) (31,0)*(31,8)->DEC(31,8)
(31,1)*(30,8)->DEC(31,9)
31. Result 0
00002.99999999999999999999988000 00000000000000000000000.00000000
0000000000000000000001.800000000

5 record(s) selected.