Data Dictionary provided by Oracle

The data dictionary provided by Oracle is used to store database information. The data dictionary can be used to understand the internal information of the Oracle database, for example, the table creator, creation time, tablespace, and user access permissions. DBAs must fully understand the database information when encountering problems, so that they can make full use of the data dictionary. Oracle has two types of data dictionary: the first type, static data dictionary. Static data dictionary does not change as user access changes. Www.2cto.com a. View starting with USER. These views are used to store information about various database objects owned by the current user. B. View starting with ALL. These views are used to store information about various database objects that can be accessed by the current user. The current user may not have these objects, but may have access permissions for these objects. C. View starting with DBA. These views are used to save information about all objects in the database. The current user must have the permissions to access the database (generally, the DBA permission is required) to view the data in these views.
Because the data dictionary is owned by SYS users, by default, only SYS users or users with DBA permissions can query all views in the data dictionary. Category 2: Dynamic Data dictionary. The Dynamic Data Dictionary changes based on the changes in user access, and also changes with the changes in database performance. The dynamic views of Oracle start with v $. For example, the view of v $ session lists the details of the current session.