Oracle7 Server Reference Manual
Dynamic Performance Tables
The Oracle7 Server contains a set of underlying tables that are maintained by the Server and accessible to the DBA user SYS. These tables are called dynamic performance tables because they are continuously updated while a database is open and in use, and their contents relate primarily to performance.
Although these tables appear to be regular database tables, they are not. Like ROWIDs and ROWNUMs, these tables may be selected from, but never updated or altered.
The file CATALOG.SQL contains definitions of the views and public synonyms for the dynamic performance tables. You must run CATALOG.SQL to create these views and synonyms.
V$ Views
Views created on the dynamic performance tables are identified by the prefix V_$. Public synonyms for these views have the prefix V$. DBAs or users should only access the V$ objects, not the V_$ objects.
The dynamic performance tables are used by Server Manager, which is the primary interface for accessing information about system performance.
Suggestion: Once the instance is started, the V$ views are accessible. The database does not have to be mounted or open. One important consequence of this fact is that the V$LOG view can be used to identify log files needed for recovery.
Warning: Information about the dynamic performance tables is presented for completeness only; this information does not imply a commitment to support these tables in the future.
Access to the Dynamic Performance Tables
After installation, only username SYS has access to the dynamic performance tables. However, access to these tables is required for any user needing to view the MONITOR displays available in command-line mode of Server Manager.
Granting Access to All Tables
The UTLMONTR.SQL script can be run to grant access to PUBLIC on all of the dynamic performance tables needed to view MONITOR displays.
For information on running UTLMONTR.SQL on your system, see your operating system specific Oracle documentation.
Granting Access on Selected Tables
If any user other than SYS wants to use Server Manager's MONITOR functions, that user needs access to one or more of the dynamic performance tables.
For more information, see Oracle7 Server Utilities.