Looking help in Default clause with CASE statement ?

Question

I have a table perform(timings date , Mor_Eve varchar2(20) )
Requirements is
(a) If time in timing column is < 12:00 then automatically insert 'MORNING' in Mor_Eve column
ELSE
automatically insert 'EVENING' in Mor_Eve column.
Is there any way of using default clause in create table that insert Morning or Evening in the Mor_Eve column automatically depending on the Timings column ?

Answer 1

Hi,
Welcome to the forum!
All the responses above are good.
Why do you need to store this at all?
If you want to display it automatically, create a view, like this:
CREATE OR REPLACE VIEW     perform_v
AS
SELECT     timings
,     CASE     TO_CHAR (timings, 'AM')
         WHEN  'AM'     THEN  'MORNING'
         WHEN  'PM'     THEN  'EVENING'
               ELSE  'NOT ENTERED'     -- Skip this line if you want NULL
     END     AS mor_eve
FROM     perform
;Always do DML on the table, but query the view when you want to see mor_eve.
I'm not saying there's no reason to store this; I'm just asking if you have one.
If you must store it, a DEFAULT clause won't work.
Starting in Oracle 11, you can have a virtual column. (You can have an index on a virtual column, but why would you want an index on a column that only had 2 values?)
In any version, you can write a trigger that autmoatically populates the mor_eve column whenever you INSERT or UPDATE.