
7.3 Tools for Tuning Queries 201
Chapter 7
SQL code is rare in mission-critical OLTP-type databases. Most OLTP
databases are controlled by applications.
The V$SESSION_EVENT performance view provides wait events for
sessions for the entire life of the session. The V$SESSION_WAIT perfor-
mance view provides the same information, but as the wait events are
occurring; it also provides access to deeper layers using parameter pointer
values as shown in Figure 7.20. The V$SESSION_EVENT view is effec-
tively an accumulation of wait events for sessions during the life of those
sessions. Thus, V$SESSION_EVENT could be used to isolate sessions
causing specific problems. ...