Scott Selikoff wrote:For most people, I recommend taking separate OCA and OCP exams, rather than the 1Z0-813 upgrade exam. While Jeanne is correct, it is more expensive, from an educational perspective taking an easier OCA exam followed by a more difficult OCP exam is the more gradual curve. In other words, the OCA gives you practice taking an Oracle exam and gives you an idea of how well you know the material. For example, if you pass but score low on the OCA exam, you should study a lot more before taking the OCP exam.
Also, the 1Z0-813 upgrade exam includes some topics, like WatchService and DirectoryStream, that are no longer on the full exam. For DirectoryStream, Java 8 stream methods are often preferred now. In other words, the upgrade exam includes topics that are no longer best practices since the introduction of streams.
That said, if you are well versed in Java 8 and hold an older certification, then the upgrade exam may be best. Alternatively, those who are experienced in Java but completely new to Java 8, taking the OCA exam first may be a better choice.