Convert from NUMBER to DATE

Question

I have data in one table that has the columns DAY,MONTH,YEAR in datatype NUMBER. I am wanting to convert that to DATE datatype and concate the month,day, and year. Can someone help me please? Thanks
SELECT TO_DATE(month||day||year,'MM/DD/YYYY')
FROM DATA_TABLE;

Answer 1

Hi,
Unfortunately, TO_DATE doesn't accept NUMBERs as arguments. You have to convert them to characters first, like this:
SELECT  TO_DATE ( TO_CHAR (month, '00') ||
                  TO_CHAR (day,   '00') ||
                  TO_CHAR (year,  '0000)     -- not '00', as originally posted
                , ' MM DD YYYY'
FROM  DATA_TABLE;Edited by: Frank Kulash on Jan 15, 2009 10:18 AM
This assumed the full year was stored, e.g. 2009. It turns out that OP is actually storing only the last two digits, which caused ORA-01841 errors. In that case
code}
SELECT TO_DATE ( TO_CHAR (month, '00') ||
TO_CHAR (day, '00') ||
TO_CHAR (year, '00)
, ' MM DD RR'
FROM DATA_TABLE;
is correct.