UPDATE TIPOOPERAC
SET IDREGESPECIAL = 'N'
WHERE IDREGESPECIAL is null
/

COMMIT
/

ALTER TABLE TIPOOPERAC MODIFY IDREGESPECIAL DEFAULT 'N' NOT NULL
/

ALTER TABLE TIPOOPERAC ADD CONSTRAINT CKC_IDREGESPECIAL_TIPOOPERAC CHECK (IDREGESPECIAL IN ('S','N'))