A: The data dictionary view name is generally used in the plural, while the dynamic performance view name is generally used in the singular, such as dba_tablepsaces vs V $ tablespace.
B: The data dictionary view can be accessed only when the database is open, while some dynamic performance views can be used when the database is not open.
C: The column information displayed in the data dictionary view is generally in upper case, while that in the dynamic performance view is generally in lower case.
D: The information in the data dictionary view is static and will not be lost after the database is closed. The information in the dynamic performance view is dynamic and will be lost after the instance is closed.
Get the definition of dynamic performance view: Select * from V _ $ fixed_view_definition;
Get the definition of the data dictionary View:
1. Select * From dba_views where view_name = 'dba _ tables ';
2. Select dbms_metadata.get_ddl ('view', 'dba _ tables ') from dual;
3. In Oracle 10 Gb, you can also use em to display metadata information.