With Firebird 2.1 and databases with ODS 11.1 (and higher) Firebird introduces the ability to monitor server-side activity happening inside a particular database.
Complete database monitoring is available to SYSDBA and the database owner. Regular users are restricted to the information about their own attachments only—other attachments are invisible to them.
Available monitoring tables since Firebird 2.1 and ODS 11.1:
Reference: Firebird 2.1 Release Notes
With Firebird 2.5 and databases with ODS 11.2 (and higher) Firebird adds the following new monitor tables
Reference: Firebird 2.5 Release Notes