How can I couple many times the same input parameter? How does it work?

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WebRatio provides the chance to couple many times the same input parameter with different output parameters. This is useful, for example, when you have different operation chains that end in the same unit. The figure shows a sample model. The data unit shows the new company, if the user clicked on the New button. Otherwise the unit shows the modified unit. In both cases the operation chain provides the company primary key to the data unit. For this reason, you have to make a particular coupling on the OK link entering the data unit. You have to couple the key condition one time for the primary key coming from the create unit and another time for the primary key coming from the modify unit. The coupling dialog shows you only a field to make the coupling. To add another field for the same condition you have to click on the Add Input Parameter () button and make the other coupling.

At runtime, the unit takes the first input parameter which is not null and uses it to compute itself. In this way you can couple the same input parameter many times, but only a single value is really valid and used by the unit.