Which view would you examine next to pinpoint the problem that is causing this performance issue?

A user, SCOTT, complains that his database session, SID 249, is extremely slow in processing transactions. You check the ADDM report and do not find any overall database performance issues.
You decide to check the wait events, specifically in SCOTT’s session and issue the following command:
SQL>SELECT wait_class_id, wait_class, total_waits, time_waited FROM v$session_wait_class
WHERE sid = 249;
View Exhibit1 and examine the output.
You note that the APPLICATION wait class is the second most expensive wait class after the IDLE wait class.
You issue the following query to identify individual waits in the APPLICATION wait class:
SQL>select event, total_waits, time_waited
from v$system_event e, v$event_name n
where n.event_id = e.event_id
and wait_class_id = 4217450380;
View Exhibit2 and examine the output.
Which view would you examine next to pinpoint the problem that is causing this performance issue?
Exhibit 1 (exhibit):
Exhibit 2 (exhibit):

A user, SCOTT, complains that his database session, SID 249, is extremely slow in processing transactions. You check the ADDM report and do not find any overall database performance issues.
You decide to check the wait events, specifically in SCOTT’s session and issue the following command:

SQL>SELECT wait_class_id, wait_class, total_waits, time_waited FROM v$session_wait_class
WHERE sid = 249;

View Exhibit1 and examine the output.


You note that the APPLICATION wait class is the second most expensive wait class after the IDLE wait class.
You issue the following query to identify individual waits in the APPLICATION wait class:

SQL>select event, total_waits, time_waited
from v$system_event e, v$event_name n
where n.event_id = e.event_id
and wait_class_id = 4217450380;

View Exhibit2 and examine the output.


Which view would you examine next to pinpoint the problem that is causing this performance issue?

A.
DBA_HIST_SESSMETRIC_HISTORY – to find the highest value metrics in the session

B.
V$SQLAREA statistics – to find the SQL statements with the highest number of executions

C.
V$SESS_TIME_MODEL – to identify whether the SQL statements in the session were spending more of execution time in parsing or waiting for the CPU

D.
V$EVENT_HISTOGRAM – to determine whether the TIME_WAITED is evenly distributed across the occurrences of the wait or whether some waits for the events were very long whilst others were short indicating more erratic response times.



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max

max

D as it is the sole which mentions ‘TIME_WAITED’ which is where to lock for 388855 (Total amount of time waited for the event (in hundredths of a second).