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If multiple requests modify the same entity the result is undetermined. The worst case behaviour observed is when concurrent access produces duplicates of that entity - the result is that no further REST queries (GET/POST/DELETE ...) to this entity are possible and the entity becomes inaccessible. Afterwards only a manual intervention in the database can restore proper service behaviour. Access the data concurrently at your own risk.
It is recommended that at all times there is only 1 client calling the A&AI REST services.
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