41. Live upgrade on executive node

This is a special case for system providers. If a system provider has come up with a system with all features developed and could load assembly codes on a live system such as APY.

The system provider could preconfigure database with all fields, tables and clear protocols between subsystems. Each subsystem is a feature communicating with other systems using a predefined dispatching protocol interface.

System provider can deploy a full database with tables and fields. If customers didn’t want a feature, the corresponding tables and fields would be empty. That subsystem’s codes would not be loaded.

If customer bought a feature at later date, system providers only need to populate those database fields, database tables, and load assembly codes of that subsystem on the executive node. After that they only need to activate the subsystem by a command.

* Notes - September 11, 2018: Creating a new table in a live node is probably fine, but creating a new field of a table would require the command "Alter Table ..", which may cause interruption in service.