Which two statements describe data dictionary views?

Question

Options

• AThey are stored in the SYSTEM tablespace.
• BThey are based on virtual tables.
• CThey are owned by the SYS user.
• DThey speed up query and data manipulation language (DML) operations.
• EThe VSFIXED_TABLEview can be queried to list the names of these views.

• A
  83% (30)
• B
  6% (2)
• D
  8% (3)
• E
  3% (1)

Explanation

https://docs.oracle.com/database/121/CNCPT/datadict.htm#CNCPT1220 Storage of the Data Dictionary The data dictionary base tables are the first objects created in any Oracle database. All data dictionary tables and views for a database are stored in the SYSTEM tablespace. Because the SYSTEM tablespace is always online when the database is open, the data dictionary is always available when the database is open. How Oracle Database Uses the Data Dictionary The Oracle Database user SYS owns all base tables and user-accessible views of the data dictionary. Data in the base tables of the data dictionary is necessary for Oracle Database to function. Therefore, only Oracle Database should write or change data dictionary information. No Oracle Database user should ever alter rows or schema objects contained in the SYS schema because such activity can compromise data integrity. The security administrator must keep strict control of this central account. Overview of the Dynamic Performance Views Throughout its operation, Oracle Database maintains a set of virtual tables that record current database activity. These views are dynamic because they are continuously updated while a database is open and in use. The views, also sometimes called V$ views because their names begin with V$, contain information such as the following: - System and session parameters - Memory usage and allocation - File states (including RMAN backup files) - Progress of jobs and tasks - Statistics and metrics The dynamic performance views have the following primary uses: - Oracle Enterprise Manager uses the views to obtain information about - Administrators can use the views for performance monitoring and Contents of the Dynamic Performance Views Dynamic performance views are sometimes called fixed views because they cannot be altered or removed by a database administrator. However, database administrators can query and create views on the tables and grant access to these views to other users. SYS owns the dynamic performance tables, whose names begin with V_$. Views are created on these tables, and then public synonyms prefixed with V$. The V$FIXED_TABLE view contains information about all of the dynamic performance tables and views. For almost every V$ view, a corresponding GV$ view exists. In Oracle Real Application Clusters (Oracle RAC), querying a GV$ view retrieves the V$ view information from all qualified database

No community discussion yet for this question.