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Oracle: DBMS_SYSTEM.SET_SQL_TRACE_IN_SESSION

set_sql_trace_in_session is just a convenience function to set diagnostic event 10046 (with level 1) in a session.

Using dbms_system.set_sql_trace_in_session, it is possible to enable tracing of SQL statement execution in other session.

For the own session, one might consider using

alter session set sql_trace=true;

Trace SQL execution in the entire instance:

alter system set sql_trace=true;

See also