A start is a starting point of the flow represented in the diagram.
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A start can be created in a choreography diagram with any of the following target languages:
In decomposed processes, only one start is allowed per diagram, except for analysis business process diagrams. The Start tool is unavailable if a start symbol already exists. You should not use the same start in two diagrams, and you cannot create shortcuts of starts.
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Activity Diagram - one or more per diagram
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Statechart Diagram - one or more per diagram
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Interaction Overview Diagram - one only per diagram
Note:
The start is compared and merged in the Merge Model feature, which checks that there is no additional start in decomposed processes
.