How to identify connected Users?

Hello all,

is there any way to identify users which are currently connected to the
database? Does perhaps even exist a method to notify this users (e.g. to
close the connection)?

Thanks in advance and best regards,

Jens

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Jens Hartwig
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debis Systemhaus GEI mbH
10875 Berlin
Tel.     : +49 (0)30 2554-3282
Fax      : +49 (0)30 2554-3187
Mobil    : +49 (0)170 167-2648
E-Mail   : jhartwig@debis.com
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