Adding primary key column in populated table

Question

Hi all,
I am trying to add a column into a table which is already populated. The column which needs to be added has to be Primary Key.
As expected, oracle popped up the error (ORA-01758) that, a NOT NULL column cannot be added unless the table is empty.
One possibe way is to create a new temp table and then transfer all the current data...renaming the temp table later.
Is there any other way to accomplish this task?
Thanks

Answer 1

Hello,
As error suggested you cannot add a not null constraint on new column to table which is already populated. What else you can do beside you got fairly simple and quick idea of creating a temp table and moving data?
You can add new column but null, update the column with the values and alter the table marking column as not null. But your idea of empty temp table is simple and quick one.
CREATE TABLE my_objects
AS
   SELECT 'my_new_column' my_new, owner
   FROM all_objects
   WHERE ROWNUM < 1;
_Not Null_
ALTER TABLE MY_OBJECTS
MODIFY(MY_NEW  NOT NULL);
_Primary key_
ALTER TABLE MY_OBJECTS
ADD CONSTRAINT MY_OBJECTS_PK
PRIMARY KEY
(MY_NEW);Regards