CWM11 — Logical-physical deployment modeling

DataManager contains a reference to the specific data (at the schema level) that is being managed but is constrained to be a DeployedComponent on a specific Machine. Though a DataManager refers to the Component that it 'instantiates' there is nothing associated with Component that allows one to record what data it can manage.

For example, I would like to be able to create an element called "Peopleware Payroll Application" which references the relational schema for the application. This should be possible without having to say anything about its deployment onto specific machines.

A separate but related point is the lack of support for physical databases. For example, When deploying an application I then want to be able to say what physical database it's using. The value of tracking this is for backup purposes etc, and the fact that actual WarehouseOperations will need to be applied to specific databases.

Proposed resolution

Add new class 'PhysicalDatabase' to SoftwareDeployment Model; this will inherit from Package and will have a many-to-many association 'LogicalPhysical' with Package, and be contained by Machine (as for DeployedComponent). [May want a subslcass of Dependency between PhysicalDatabases to represent replication/federation/partitioning. Or alternatively use containment by one 'abstract' PhysicalDatabase of others to represent this, though this does not allow the exact relationship to be expressed.]

Move the 'dataPackage' reference from DataManager to SoftwareSystem. Add new many-to-many reference 'databases' to DataManager with target type PhysicalDatabase.

see below