Can someone elaborate what is the use of the Instance ID field in the Application Metadata form? Why does it have to be -1? Also, can it be modified (say, using a workflow) at a later point of time while using the application?… Is an instance created when we put -1 as the Instance ID, which changes later on? If yes, can that be explicitly changed by some means? And what is the purpose behind it?
If you specify an application instance ID, that value will be used as a context ID for the primary data sources on your model. It works the same way as using the triplet-ds-context-id for child data sources. The difference is that application instance ID is a fixed value for the application and it will not be changed. The value -1 means that the instance ID is not used for this application. This is an application metadata, so there is no reason for a workflow to change that value.