Strange way... keep date in a float????

Question

Hello everybody,
i have a big problem converting numbers to date.
The reason is that i dont understand the format or method of the save.
I now the a determined float number correspond to a date and i want to transform
de float that is keep in the oracle db to date.
Example (DD-MM-YYY)
13-10-2006 ============== 131467789
16-10-2006 ============== 131467792
14-11-2006 ============== 131468046
17-11-2006 ============== 131468049
I have tried everything (timestamp, unix timestamp, etc)
Somebody please help me
thanks

Answer 1

Hi,
I'm not an expert on encoding, but when you look on your examples:
A)Difference between the values for dates within the same month equals the number of days between corresponding dates (in both cases)
16-10-2006 - 13-10-2006 = 3 days
131467792 - 131467789 = 3
B)But the same is NOT true for dates in different months.
14-11-2006 - 16-10-2006 = 29 days
131468046 - 131467792 = 254
To find the encoding of months, I would need a pair of datums with the same day and year, but different months. There is none in your example, but if A) is a valid assumption, than:
valueFor(14-10-2006)=valueFor(13-10-2006)+1 = 131467789 + 1=131467790
Then:
valueFor(14-11-2006) - valueFor(14-10-2006)= 131468046 - 131467790 = 256
A magical hexadecimal number, isn't it?
So I tried converting your numbers into hexadecimal:
valueFor(14-11-2006) = 131468046 = 7D60B0E HEX
Now it's easy. Go from the end backwards and convert the bytes back to decimal:
0E HEX = 14 <= Day
0B HEX = 11 <=Month
07 D6 HEX = 2006 <= Year
It works for all the dates given by you.
So:
First (highest) two bytes = year
3rd byte = month
4th byte = day
If n is your number, then the conversion is:
day = mod(n,256)
month = trunc(mod(n,256*256)/256)
year = trunc(n/(256*256))
or the other way:
n = day + 256 * month + (256*256) * year
But as I said, I'm not an expert on encoding and you should definitely test this hypothesis on other dates and coresponding encoded values - preferrably from different months and years.