Oracle used a whole book to illustrate Valut, interested in children's shoes can refer to http://docs.oracle.com/cd/E11882_01/server.112/e23090/toc.htm, I personally think it does not need It is only right to know that there is such a thing as a thorough understanding of it.
From a macro perspective, Vault is part of the Oracle database security Domain-access control, and can refer to the [Oracle] Data Security overview
Unlike Vpd,ols, the main purpose of vault in the actual production environment is to prevent abuse of authority with the SYS account DBA. In the absence of vault, DBAs can view data at will, which is not allowed for some businesses (especially in the financial sector), and with vault, you can control the DBA's inability to access the core data of the application, as shown in the following illustration:
There are now fields of HR and fin, and even DBAs with SYS privileges are not able to access these two areas, and only users in the appropriate field can access data in a particular area. This completely resolves the problem of DBA authority abuse.
Here does not explain the vault configuration in detail, most people just understand its role on it, the real business to go back to the book mentioned above, the technology of this thing is not finished, and sometimes to understand that enough:
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