Oracle PL/SQL modify column DEFAULT_LENGTH attribute

Question

I have attribute DEFAULT_LENGTH in bellow select:

SELECT 
  TABLE_NAME,
  COLUMN_NAME,
  DATA_DEFAULT,
  DEFAULT_LENGTH
FROM all_tab_columns
WHERE TABLE_NAME LIKE 'TEST2';

For changing DATA_DEFAULT I used below syntax:

ALTER TABLE TEST2 MODIFY (COL1 DEFAULT 'en');

How can I change with similar alter option syntax DEFAULT_LENGTH?

Thanks!

Answer 1

"How can I change with similar alter option syntax DEFAULT_LENGTH?"

You don't need to. DEFAULT_LENGTH is derived from the length of the DATA_DEFAULT.