i'm planing to pass the OCA 11g: Exam 1Z0-051 & 1Z0-052Planning to pass is a good start. I generally recommend against planning to fail.
would u pls let me know whether these books are enoughI can tell you that people have used those books as sources and passed the tests. People have also used those books and failed the tests. The source used to study for the exam matters much less than does the person doing the studying. If the question that you are asking is whether those books contain sufficient information in them for someone to use them to pass the exam, then the answer is a resounding yes. That said, I always recommend using multiple sources when studying for certifications. You can find a number of links to free study sources -- such as the relevant Oracle manuals, Oracle Learning Library articles and other such material at www.oraclecertificationprep.com. Click into 'Exam Info' and then select the test you are interested in. For example, for 1Z0-052, the site contains links to the following OLL articles: