Exam 1z0-148 topic 1 question 49 discussion

Refer to the Exhibit.

Examine this procedure created in a session where PLSQL_OPTIMIZE_LEVEL =2:

PL/SQL tracing in enabled in a user session using this command:
EXEC DBMS_TRACE.SET_PLSQL_TRACE (DBMS_TRACE.TRACE_ENABLED_LINES)
The procedure is executed using this command:

EXEC PRC_1 -
Examine the exhibit for the content of the PLSQL_TRACE_EVENTS table.
Why is tracing excluded from the PLSQL_TRACE_EVENTS table?