Apakah ada perbedaan antara menggunakan default dan: = di plsql

DECLARE
    blood_type CHAR DEFAULT 'O';         -- Same as blood_type CHAR := 'O';
    hours_worked    INTEGER DEFAULT 40;  -- Typical value
    employee_count  INTEGER := 0;        -- No typical value

  BEGIN
    NULL;
  END;
  /
Proud Peccary