This screen displays the actual database parameter and attribute settings being used by the processes attached to the database. Optionally, users are allowed to dynamically update certain database parameters and attributes on a single node at run time. The net effect of these changes can be examined at run time without having to restart database processes. These updates are nonpersistent. For example, when the RDM$BIND_BUFFERS logical name is defined at the process level, there is no method available for the database administrator (DBA) to examine its setting at runtime. The same is true for any database logical name and most interesting database attributes that affect runtime performance of the database. However, the Database Dashboard provides this information dynamically. The Database Dashboard facility allows you to "drive" the database faster or slower, and immediately see the impact of increasing or decreasing certain database settings. You can use the Update menu option, by typing the letter U, to change the value of a database attribute. Before you can update database attributes, you need to start your Performance Monitor session with the Options=Update qualifier and you need OpenVMS WORLD, BYPASS, and SYSNAM privileges. CAUTION You should use the Update option carefully. Oracle Rdb does not perform error checking on the updated values. Note that updates made to any attributes are not stored in the database root file. The purpose of updating attributes is to test and measure the effects of changes on the database, so that you can later make persistent changes to appropriate database attributes using interactive SQL. Database attributes are updated on the current node only. You can use the Config menu option, by typing the letter C, to display the configuration submenu. The configuration submenu provides the following options: o Use XXX notification of change Broadcast the changes to the database attributes and parameters actively or passively. The option description changes depending on which method of broadcast is current. o Notify users of previous changes Active notification means that all processes attached to the database on the node will be immediately notified that a database attribute setting has been modified and that they should reset their individual parameter values. Passive notification means that the user processes will be notified passively at intervals determined by the database software. Passive notification is the default, as it is non-intrusive to system performance. The advantage of active notification is that each database user on the node is immediately notified of the change and that the new parameter settings are immediately used. The disadvantage is that system performance may be temporarily impacted while the users respond to the notification. The advantage of passive notification is that there is no impact on the system. The disadvantage is that you have no control over when the individual processes will be notified that a particular database parameter setting has changed. When using passive notification, a broadcast notification can be performed using the "Notify users of previous changes" option of the Config submenu. The Dashboard display contains the following columns: o Current Value This column contains the current value for each database attribute. On global database screens, this is the default value being used by all processes. On per-process screens, this is the actual value being used by that particular process. o Previous Value This column contains the previous value for each database attribute. When a database attribute is dynamically updated, this column will contain the value before it was modified. o Lowest Value This column contains the lowest value for each database attribute. o Highest Value This column contains the highest value for each database attribute. o Original Value This column contains the original value for each database attribute. This column remains unchanged regardless of the changes made to the database attribute. o Chng Cnt This column contains the count of the number of changes to each database attribute. On global database screens, this count is the number of times the particular database attribute was updated by the user. On per-process screens, this count is the number of times the actual process has updated its dynamic information. The dynamic updates that users make to the database are reflected only in the Current Value column. The remaining columns reflect changes made by the current user only. You can display successive dashboards by pressing the right angle bracket (>) key or the Next Screen key. To display a previous dashboard, press the left angle bracket (<) key or the Prev Screen key. Note that you cannot go to the per-process dashboard screens. The Dashboard screen is not recorded in the binary output file produced using the Output qualifier. Consequently, this display is not available when you replay a binary file using the Input qualifier.