SQL> desc v$session_wait
Name NULL? Type
---------------------------------- -------- -----------------
SID NUMBER
SEQ# NUMBER
EVENT VARCHAR2(64)
P1TEXT VARCHAR2(64)
P1 NUMBER
P1RAW RAW(8)
P2TEXT VARCHAR2(64)
P2 NUMBER
P2RAW RAW(8)
P3TEXT VARCHAR2(64)
P3 NUMBER
P3RAW RAW(8)
WAIT_CLASS_ID NUMBER
WAIT_CLASS# NUMBER
WAIT_CLASS VARCHAR2(64)
WAIT_TIME NUMBER
SECONDS_IN_WAIT NUMBER
STATE VARCHAR2(19)

SQL> select EVENT from v$session_wait where SID=1635;

db file scattered read

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