n is either 1 (true) or 0 (false). The default value is 0.
When ViewPastData is enabled (n = 1), you can use the $VIEW command to examine data outside of InterSystems IRIS memory area. When this parameter is not enabled, the $VIEW command throws an error.
Changing This Parameter
On the Compatibility page of the Management Portal (System Administration > Configuration > Additional Settings > Compatibility), in the ViewPastData row, click Edit. Select ViewPastData to enable this setting.
Instead of using the Management Portal, you can change ViewPastData in the Config.MiscellanousOpens in a new window class (as described in the class reference) or by editing the CPF in a text editor (as described in the Editing the Active CPF section of the “Introduction to the Configuration Parameter File” chapter in this book).