Data Model

The schema dml-diagramDataModel.xsd defines the data model in a diagram. The purpose of the data model is twofold. The first use of the data model is to hold the information contained in a diagram. For example, in figure 1 below, the purpose of the data model would be to hold the information, “one”, “two” and “three” for the diagram.

Figure 11: Example diagram with data.

The second use of the data model is to define an initial state of the diagram. This initial state consists of what can be thought of as placeholder data, which an application uses to display a diagram initially before any data has been entered. Figure 2 shows an example of what a diagram might look like in an initial state containing three empty nodes. In this example, the placeholder data consists of three nodes and two connections, which will be explained shortly.

Figure 12: An empty diagram in its initial state.