Upate 2nd date field in the same table.

Question

This is probably a simple fix, but i can't seem to get it. Any help is greatly appreciated!
I need to update a field (ACC_DATE2) in the table called (DRIVERS_ACCIDENTS) and insert a formatted (ACC_DATE) field in the format [mm//dd/yyyy]
Here is what I had started, but it returns too many records.
UPDATE DRIVERS_ACCIDENTS
SET ACC_DATE2 = to_date(( SELECT DRIVERS_ACCIDENTS.ACC_DATE
FROM DRIVERS_ACCIDENTS
WHERE DRIVERS_ACCIDENTS.ID = DRIVERS_ACCIDENTS.ID) 'MM/DD/YYYY')
WHERE EXISTS
( select DRIVERS_ACCIDENTS.ID
from DRIVERS_ACCIDENTS
where DRIVERS_ACCIDENTS.ID = DRIVERS_ACCIDENTS.ID);

Answer 1

Do you want to fill ACC_DATE2 with ACC_DATE of the
same row?
If the answer is yes, this would simplify your update
statement to
UPDATE DRIVERS_ACCIDENTS
SET ACC_DATE2 = to_date(ACC_DATE, 'MM/DD/YYYY')
No it is not true! I suppose that the two columns are of type DATE.
to_date in this case will return an error. You don't have any need to use the format here. So you could say
UPDATE DRIVERS_ACCIDENTS
SET ACC_DATE2 = ACC_DATEYou should use the format when you will consult the column later!
Michel SALAIS