进程相关：
1、 求当前会话的SID，SERIAL#
SELECT Sid, Serial#
FROM V$session
WHERE Audsid = Sys_Context(USERENV, SESSIONID);
2、 查询session的OS进程ID
SELECT p.Spid "OS Thread", b.NAME "Name-User", s.PRogram, s.Sid, s.Serial#,
s.Osuser, s.Machine
FROM V$process p, V$session s, V$bgprocess b
WHERE p.Addr = s.Paddr
AND p.Addr = b.Paddr
And (s.sid=&1 or p.spid=&1)
UNION ALL
SELECT p.Spid "OS Thread", s.Username "Name-User", s.Program, s.Sid,
s.Serial#, s.Osuser, s.Machine
FROM V$process p, V$session s
WHERE p.Addr = s.Paddr
And (s.sid=&1 or p.spid=&1)
AND s.Username IS NOT NULL;
3、根据sid查看对应连接正在运行的sql
SELECT /*+ PUSH_SUBQ */
Command_Type, Sql_Text, Sharable_Mem, Persistent_Mem, Runtime_Mem, Sorts,
Version_Count, Loaded_Versions, Open_Versions, Users_Opening, Executions,
Users_Executing, Loads, First_Load_Time, Invalidations, Parse_Calls,
Disk_Reads, Buffer_Gets, Rows_Processed, SYSDATE Start_Time,
SYSDATE Finish_Time, > || Address Sql_Address, N Status
FROM V$sqlarea
WHERE Address = (SELECT Sql_Address
FROM V$session
WHERE Sid = &sid );
4、查找object为哪些进程所用
SELECT p.Spid, s.Sid, s.Serial# Serial_Num, s.Username User_Name,
a.TYPE Object_Type, s.Osuser Os_User_Name, a.Owner,
a.OBJECT Object_Name,
Decode(Sign(48 - Command), 1, To_Char(Command), Action Code # || To_Char(Command)) Action,
p.Program Oracle_Process, s.Terminal Terminal, s.Program Program,
s.Status Session_Status
FROM V$session s, V$access a, V$process p
WHERE s.Paddr = p.Addr
AND s.TYPE = USER
AND a.Sid = s.Sid
AND a.OBJECT = &obj
ORDER BY s.Username, s.Osuser
5、查看有哪些用户连接
SELECT s.Osuser Os_User_Name,
Decode(Sign(48 - Command),1,To_Char(Command),
Action Code # || To_Char(Command)) Action,
p.Program Oracle_Process, Status Session_Status, s.Terminal Terminal,
s.Program Program, s.Username User_Name,
s.Fixed_Table_Sequence Activity_Meter, Query, 0 Memory,
0 Max_Memory, 0 Cpu_Usage, s.Sid, s.Serial# Serial_Num
FROM V$session s, V$process p
WHERE s.Paddr = p.Addr
AND s.TYPE = USER
ORDER BY s.Username, s.Osuser
6、根据v.sid查看对应连接的资源占用等情况
SELECT n.NAME, v.VALUE, n.CLASS, n.Statistic#
FROM V$statname n, V$sesstat v
WHERE v.Sid = &sid
AND v.Statistic# = n.Statistic#
ORDER BY n.CLASS, n.Statistic#
7、查询耗资源的进程（top session）
SELECT s.Schemaname Schema_Name,
Decode(Sign(48 - Command),
1, To_Char(Command), Action Code # || To_Char(Command)) Action,
Status Session_Status, s.Osuser Os_User_Name, s.Sid, p.Spid,
s.Serial# Serial_Num, Nvl(s.Username, [Oracle process]) User_Name,
s.Terminal Terminal, s.Program Program, St.VALUE Criteria_Value
FROM V$sesstat St, V$session s, V$process p
WHERE St.Sid = s.Sid
AND St.Statistic# = To_Number(38)
AND (ALL = ALL OR s.Status = ALL)
AND p.Addr = s.Paddr
ORDER BY St.VALUE DESC, p.Spid ASC, s.Username ASC, s.Osuser ASC
8、查看锁（lock）情况
SELECT /*+ RULE */
Ls.Osuser Os_User_Name, Ls.Username User_Name,
Decode(Ls.TYPE,
RW, Row wait enqueue lock, TM, DML enqueue lock,
TX, Transaction enqueue lock, UL, User supplied lock) Lock_Type,
o.Object_Name OBJECT,
Decode(Ls.Lmode,
1, NULL, 2, Row Share, 3, Row Exclusive,
4, Share, 5, Share Row Exclusive, 6, Exclusive,
NULL) Lock_Mode,
o.Owner, Ls.Sid, Ls.Serial# Serial_Num, Ls.Id1, Ls.Id2
FROM Sys.Dba_Objects o,
(SELECT s.Osuser, s.Username, l.TYPE, l.Lmode, s.Sid, s.Serial#, l.Id1,
l.Id2
FROM V$session s, V$lock l
WHERE s.Sid = l.Sid) Ls
WHERE o.Object_Id = Ls.Id1
AND o.Owner <> SYS
ORDER BY o.Owner, o.Object_Name
9、查看等待（wait）情况
SELECT Ws.CLASS, Ws.COUNT COUNT, SUM(Ss.VALUE) Sum_Value
FROM V$waitstat Ws, V$sysstat Ss
WHERE Ss.NAME IN (db block gets, consistent gets)
GROUP BY Ws.CLASS, Ws.COUNT
10、求process/session的状态
SELECT p.Pid, p.Spid, s.Program, s.Sid, s.Serial#
FROM V$process p, V$session s
WHERE s.Paddr = p.Addr;
11、求谁阻塞了某个session(10g)
SELECT Sid, Username, Event, Blocking_Session, Seconds_In_Wait, Wait_Time
FROM V$session
WHERE State IN (WAITING)
AND Wait_Class != Idle;
12、查会话的阻塞
col user_name format a32
SELECT /*+ rule */
Lpad( , Decode(l.Xidusn, 0, 3, 0)) || l.Oracle_Username User_Name,
o.Owner, o.Object_Name, s.Sid, s.Serial#
FROM V$locked_Object l, Dba_Objects o, V$session s
WHERE l.Object_Id = o.Object_Id
AND l.Session_Id = s.Sid
ORDER BY o.Object_Id, Xidusn DESC;
col username format a15
col lock_level format a8
col owner format a18
col object_name format a32
SELECT /*+ rule */
s.Username,
Decode(l.TYPE, tm, table lock, tx, row lock, NULL) Lock_Level,
o.Owner, o.Object_Name, s.Sid, s.Serial#
FROM V$session s, V$lock l, Dba_Objects o
WHERE l.Sid = s.Sid
AND l.Id1 = o.Object_Id(+)
AND s.Username IS NOT NULL;
13、求等待的事件及会话信息/求会话的等待及会话信息
SELECT Se.Sid, s.Username, Se.Event, Se.Total_Waits, Se.Time_Waited,
Se.Average_Wait
FROM V$session s, V$session_Event Se
WHERE s.Username IS NOT NULL
AND Se.Sid = s.Sid
AND s.Status = ACTIVE
AND Se.Event NOT LIKE %SQL*Net%
ORDER BY s.Username;
SELECT s.Sid, s.Username, Sw.Event, Sw.Wait_Time, Sw.State,
Sw.Seconds_In_Wait
FROM V$session s, V$session_Wait Sw
WHERE s.Username IS NOT NULL
AND Sw.Sid = s.Sid
AND Sw.Event NOT LIKE %SQL*Net%
ORDER BY s.Username;
14、求会话等待的file_id/block_id
col event format a24
col p1text format a12
col p2text format a12
col p3text format a12
SELECT Sid, Event, P1text, P1, P2text, P2, P3text, P3
FROM V$session_Wait
WHERE Event NOT LIKE %SQL%
AND Event NOT LIKE %rdbms%
AND Event NOT LIKE %mon%
ORDER BY Event;
SELECT NAME, Wait_Time
FROM V$latch l
WHERE EXISTS (SELECT 1
FROM (SELECT Sid, Event, P1text, P1, P2text, P2, P3text, P3
FROM V$session_Wait
WHERE Event NOT LIKE %SQL%
AND Event NOT LIKE %rdbms%
AND Event NOT LIKE %mon%) x
WHERE x.P1 = l.Latch#);
15、求会话等待的对象
col owner format a18
col segment_name format a32
col segment_type format a32
SELECT Owner, Segment_Name, Segment_Type
FROM Dba_Extents
WHERE File_Id = &File_Id
AND &Block_Id BETWEEN Block_Id AND Block_Id + Blocks - 1;
16、求出某个进程，并对它进行跟踪
SELECT s.Sid, s.Serial#
FROM V$session s, V$process p
WHERE s.Paddr = p.Addr
AND p.Spid = &1;
Exec Dbms_System.Set_Sql_Trace_In_Session(&1, &2, TRUE);
Exec Dbms_System.Set_Sql_Trace_In_Session(&1, &2, FALSE);
17、求当前session的跟踪文件
SELECT P1.VALUE || / || P2.VALUE || _ora_ || p.Spid || .ora Filename
FROM V$process p, V$session s, V$parameter P1, V$parameter P2
WHERE P1.NAME = user_dump_dest
AND P2.NAME = instance_name
AND p.Addr = s.Paddr
AND s.Audsid = Userenv(SESSIONID)
AND p.Background IS NULL
AND Instr(p.Program, CJQ) = 0;
18、求出锁定的对象
SELECT Do.Object_Name, Session_Id, Process, Locked_Mode
FROM V$locked_Object Lo, Dba_Objects Do
WHERE Lo.Object_Id = Do.Object_Id;