- Using the Rest-API Optimize can perform custom queries against the engine for the running/completed historic activity instances
- the custom SQL-queries work on all databases
- the whole implementation is not in the public package and should not be documented
- if authorization is enabled and the request is done with basic authentication, only users that have admin rights or READ_HISTORY/ALL permission on the Process definition resource can perform queries. If the use is not authorized, he receives an appropriate response telling the user that.