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Can a participant share the database with other replicas? Yes, if participants do not work with same composition/instance at same time.
Shared database with same supported element Type: a composition will be connected to a specific participantId, so only one participant will do actions with this composition and his instances. But it can fetch all compositions that are sharing.
In a restarting scenario the participant will change the participantId, and it can still fetch compositions and instances. ACM-runtime decides who has to work with, and Participant will do actions based on the message.
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