Replace the data in the table from other table

Question

Iam creating a backup of table Order by this query:
create table orderbckup as select * from order; - this works
For the first time i have to create a orderbckup table but every month i have to replace the data in orderbckup from order table. Is there any way where i can copy the data from order and repalce the data in orderbckp - I cannot use insert as it adds the rows. Or do i need to delete the old table and create it again or can i use update. If so can anyone plz let me know

Answer 1

882431 wrote:
Iam creating a backup of table Order by this query:
create table orderbckup as select * from order; - this works
For the first time i have to create a orderbckup table but every month i have to replace the data in orderbckup from order table. Is there any way where i can copy the data from order and repalce the data in orderbckp - I cannot use insert as it adds the rows. Isn't that exactly what you want to do - add rows?
If I understand you, the problem isn't with adding new rows; the problem is how to remove the old rows.
Or do i need to delete the old table and create it again or can i use update. If so can anyone plz let me knowInstead of dropping the table and re-creating it, you can TRUNCATE the table and then use INSERT:
TRUNCATE TABLE orderbackup;
-- At this point, orderbackup has 0 rows
INSERT INTO  orderbackup
SELECT  *
FROM    orders       -- ORDER is a reserved word in Oracle, so it's not a good table name
;TRUNCATE TABLE is faster than DELETing all the rows, because it doesn't save redo information. (That means you can't ROLLBACK a TRUNCATE statement, but you can rollback a DROP TABLE statement, either.)