Question : Oracle  +  plsql

I've a small doubt, if any body knows pls give me some solution.
In my oracle table i've 2 columns AMOUNT & DECIMAL. So based on the decimal value, i've to convert the amount as mentioned in the FINAL_RESULT colum.
Ex: For amount 10000 its decimal places are 2, so i've give final_result as 100.00
see the following data,
Amount     Decimal        Final_Result
------          -------             --------------
10000          2             100.00
19388          3             19.388
344334         4            34.4334
Like that n no. of Amounts are there & n no. of decimal are there
How can i achieve the above Final_Result based on the Amount & Decimal columns.
Its very urgent.........   reply pls.   Give me the sol....

Answer : Oracle  +  plsql

The statement is starting to look a little clumsy, but try this as it appears to work:

select to_char(amount/power(10,decimal),'99999999990'||substr('.',1,decimal)||rpad('0',decimal,'0'))
from mytable;

The 2nd argument of the to_char function is used to supply the format mask, which determines how many decimal places to display.  In the above statement this format mask is constructed using:

'99999999990'||substr('.',1,decimal)||rpad('0',decimal,'0'))

The '99999999990' literal can be as large has you like to handle the largest number stored in your table i.e. just add extra or fewer 9's as required.  The substr simply adds a decimal point when the value of decimal > 0.  A decode or case could also be used, but the substr is shorter.  The rpad adds the required number of decimal places to the format mask.