ORACLE中可以通過v$session表檢視當前有效的session資訊，並且可以通過v$session的sql_id或sql_address通過關聯查詢v$sql檢視當前正在執行的sql語句；

 如果想檢視session近期執行的sql語句,可以通過v$active_session_history表中的sql_id檢視近期歷史執行的sql語句,要求資料庫的liberary沒有被fresh。

1. SELECT b.sql_text, --content of SQL

2. a.machine, --which machine run this code

3. a.username, a.module, -- the method to run this SQL

4. c.sofar / totalwork * 100, --conplete percent

5. c.elapsed_seconds, --run time

6. c.time_remaining --remain to run time

7. FROM v$session a, v$sqlarea b, v$session_longops c

8. WHERE a.sql_hash_value = b.hash_value(+) AND a.SID = c.SID(+)

9. AND a.serial# = c.serial#(+)

10. --AND a.sid=139

Oracle 最近執行過的sql語句:

1. SELECT sql_text, last_load_time

2. FROM v$sql

3. WHERE last_load_time IS NOT NULL

4. ORDER BY last_load_time DESC

    其它，

SELECT sql_text,last_load_time FROM v$sql order by last_load_time desc;

SELECT   sql_text, last_load_time FROM v$sql WHERE last_load_time IS NOT NULL and sql_text like 'select%' ORDER BY last_load_time DESC;
 

SELECT   sql_text, last_load_time FROM v$sql WHERE last_load_time IS NOT NULL and sql_text like 'update%' ORDER BY last_load_time DESC;

SELECT   sql_text, last_load_time FROM v$sql WHERE last_load_time IS NOT NULL and last_load_time like' 14-06-09%' ORDER BY last_load_time DESC;

監控concurrent 正在執行的sql
 

1. SELECT a.sid, a.serial#, b.sql_text

2. FROM v$session a, v$sqltext b

3. WHERE a.sql_address = b.address

4. --AND a.sid = <...>

5. ORDER BY b.piece

正在執行的
 

1. SELECT a.username, a.sid,b.SQL_TEXT, b.SQL_FULLTEXT

2. FROM v$session a, v$sqlarea b

3. where a.sql_address = b.address

執行過的

1. SELECT b.SQL_TEXT,b.FIRST_LOAD_TIME,b.SQL_FULLTEXT

2. FROM v$sqlarea b

3. WHERE b.FIRST_LOAD_TIME between '2009-10-15/09:24:47' and

4. '2009-10-15/09:24:47' order by b.FIRST_LOAD_TIME

（此方法好處可以檢視某一時間段執行過的sql，並且 SQL_FULLTEXT 包含了完整的 sql 語句）

其他

1. SELECT OSUSER,PROGRAM,USERNAME,SCHEMANAME,B.Cpu_Time,STATUS,B.SQL_TEXT

2. FROM V$SESSION A LEFT JOIN V$SQL B ON A.SQL_ADDRESS=B.ADDRESS AND A.SQL_HASH_VALUE=B.HASH_VALUE ORDER BY b.cpu_time desc

1. SELECT address, sql_text, piece

2. FROM v$session, v$sqltext

3. WHERE address = sql_address

4. -- and machine = < you machine name >

5. ORDER BY address, piece

查詢前十條效能差的sql

1. SELECT * FROM (SELECT PARSING_USER_ID,EXECUTIONS,SORTS,

2. COMMAND_TYPE,DISK_READS,sql_text FROM v$sqlarea

3. ORDER BY disk_reads DESC )WHERE ROWNUM<10 ;

檢視佔io較大的正在執行的session 
 

1. SELECT se.sid,se.serial#,pr.SPID,se.username,se.status,

2. se.terminal,se.program,se.MODULE,se.sql_address,st.event,st.

3. p1text,si.physical_reads,

4. si.block_changes FROM v$session se,v$session_wait st,

5. v$sess_io si,v$process pr WHERE st.sid=se.sid AND st.

6. sid=si.sid AND se.PADDR=pr.ADDR AND se.sid>6 AND st.

7. wait_time=0 AND st.event NOT LIKE '%SQL%' ORDER BY physical_reads DESC

    以sysdba登入

sqlplus / as sysdba;

執行如下sql檢視最近3天執行的delete和truncate操作

  SELECT c.username,    
         a.program,      
		 b.sql_text,         
		 b.command_type,         
		 a.sample_time   
		 FROM dba_hist_active_sess_history a
         JOIN dba_hist_sqltext b
            ON a.sql_id = b.sql_id
         JOIN dba_users c
            ON a.user_id = c.user_id
   WHERE     a.sample_time BETWEEN SYSDATE - 3 AND SYSDATE
         AND b.command_type IN (7, 85)
ORDER BY a.sample_time DESC;

    搜出結果還算有用，雖然都是業務刪除，記錄下
 

--查詢Oracle正在執行的sql語句及執行該語句的使用者

SELECT b.sid oracleID,
       b.username 登入Oracle使用者名稱,
       b.serial#,
       spid 作業系統ID,
       paddr,
       sql_text 正在執行的SQL,
       b.machine 計算機名
FROM v$process a, v$session b, v$sqlarea c
WHERE a.addr = b.paddr
   AND b.sql_hash_value = c.hash_value

--檢視正在執行sql的發起者的發放程式

SELECT OSUSER 電腦登入身份,
       PROGRAM 發起請求的程式,
       USERNAME 登入系統的使用者名稱,
       SCHEMANAME,
       B.Cpu_Time 花費cpu的時間,
       STATUS,
       B.SQL_TEXT 執行的sql
FROM V$SESSION A
LEFT JOIN V$SQL B ON A.SQL_ADDRESS = B.ADDRESS
                   AND A.SQL_HASH_VALUE = B.HASH_VALUE
ORDER BY b.cpu_time DESC

--查出oracle當前的被鎖物件

SELECT l.session_id sid,
       s.serial#,
       l.locked_mode 鎖模式,
       l.oracle_username 登入使用者,
       l.os_user_name 登入機器使用者名稱,
       s.machine 機器名,
       s.terminal 終端使用者名稱,
       o.object_name 被鎖物件名,
       s.logon_time 登入資料庫時間
FROM v$locked_object l, all_objects o, v$session s
WHERE l.object_id = o.object_id
   AND l.session_id = s.sid
ORDER BY sid, s.serial#;

--kill掉當前的鎖物件可以為

alter system kill session 'sid， s.serial#‘;