Question about rounding a decimal

Question

Hi, I've got a requirement that says that if I've got a decimal number, say,
16.15446
I should display it as 16.16
The values I'm provided with will always have 5 decimal places.
If I'm provided with 16.15552, I should display it as 16.16 too.
obviously I tried:
select round(16.15446,2) as test_value from dual
TEST_VALUE
     16.15
1 row selected.But obviously it's not what I expected.
Any suggestions?

Answer 1

Actually, that's probably the "correct" answer.
0.15446 is closer to 1.5 than it is to 1.6, so rounding down to 1.5 is the 'right' thing to so.
But if your rounding rules are different, something like this might do:
select case when mod(substr(16.15667,5,1),2)=1 then round(16.15667,2) else round(16.15667-0.01,2) end from dual;You obviously need to substitute in appropriate values all the way through that, but if you plug in 16.15552, you get:
SQL> select case when mod(substr(16.15552,5,1),2)=1 then round(16.15552,2) else round(16.15552-0.01,2) end from dual;
CASEWHENMOD(SUBSTR(16.15552,5,1),2)=1THENROUND(16.15552,2)ELSEROUND(16.15552-0.0
                                                                           16.16And for your original number:
SQL> select case when mod(substr(16.15552,5,1),2)=1 then round(16.15552,2) else round(16.15552-0.01,2) end from dual;
CASEWHENMOD(SUBSTR(16.15446,5,1),2)=1THENROUND(16.15552,2)ELSEROUND(16.15446-0.0
                                                                           16.16