Foreign Key (ON DELETE CASCADE)

Look at this:

create TABLE BGW.YYY (
    ID number not null,
    PARENT_ID number not null references XXX(ID),
    PASSWORD varchar2(254) null
) TABLESPACE SSS;

Is it the same as the following two DDL?

create TABLE BGW.YYY (
    ID number not null,
    PARENT_ID number not null,
    PASSWORD varchar2(254) null
) TABLESPACE SSS;

ALTER TABLE BGW.YYY ADD (
    CONSTRAINT FK_YYY FOREIGN KEY (PARENT_ID)
    REFERENCES BGW.XXX (ID)
);

Do I need to add ON DELETE CASCADE to the ALTER TABLE statement to make it equivalent to the first CREATE TABLE statement?