在 Oracle 資料庫日常維護與效能調優中,掌握正在執行與已執行的 SQL 語句查詢技巧至關重要。本文整理了多種實用查詢語句,涵蓋即時監控、歷史追溯、鎖定分析與效能排查等場景,助您快速定位問題。
結合 v$process、v$session 與 v$sqlarea 視圖,可即時掌握會話執行狀態:
SELECT b.sid oracleID,
b.username 登錄Oracle用戶名,
b.serial#,
spid 操作系統ID,
paddr,
sql_text 正在執行的SQL,
b.machine 計算機名
FROM v$process a, v$session b, v$sqlarea c
WHERE a.addr = b.paddr
AND b.sql_hash_value = c.hash_value;
僅需關聯 v$session 與 v$sqlarea 即可獲取核心資訊:
SELECT a.username, a.sid, b.SQL_TEXT, b.SQL_FULLTEXT FROM v$session a, v$sqlarea b WHERE a.sql_address = b.address;
利用 FIRST_LOAD_TIME 欄位可精準回溯特定時段執行過的 SQL,SQL_FULLTEXT 確保長語句完整顯示:
SELECT b.SQL_TEXT, b.FIRST_LOAD_TIME, b.SQL_FULLTEXT FROM v$sqlarea b WHERE b.FIRST_LOAD_TIME BETWEEN '2016-10-1/09:24:47' AND '2016-10-1/09:24:47' ORDER BY b.FIRST_LOAD_TIME;
SELECT OSUSER, PROGRAM, USERNAME, SCHEMANAME, B.Cpu_Time, STATUS, B.SQL_TEXT FROM V$SESSION A LEFT JOIN V$SQL B ON A.SQL_ADDRESS = B.ADDRESS AND A.SQL_HASH_VALUE = B.HASH_VALUE ORDER BY b.cpu_time DESC;
SELECT address, sql_text, piece FROM v$session, v$sqltext WHERE address = sql_address ORDER BY address, piece;
SELECT OSUSER 電腦登錄身份,
PROGRAM 發起請求的程序,
USERNAME 登錄系統的用戶名,
SCHEMANAME,
B.Cpu_Time 花費cpu的時間,
STATUS,
B.SQL_TEXT 執行的sql
FROM V$SESSION A LEFT JOIN V$SQL B
ON A.SQL_ADDRESS = B.ADDRESS AND A.SQL_HASH_VALUE = B.HASH_VALUE
ORDER BY b.cpu_time DESC;
SELECT l.session_id sid, s.serial#, l.locked_mode 鎖模式,
l.oracle_username 登錄用戶, l.os_user_name 登錄機器用戶名,
s.machine 機器名, s.terminal 終端用戶名,
o.object_name 被鎖對象名, s.logon_time 登錄數據庫時間
FROM v$locked_object l, all_objects o, v$session s
WHERE l.object_id = o.object_id
AND l.session_id = s.sid
ORDER BY sid, s.serial#;
ALTER SYSTEM KILL SESSION 'sid, serial#';
SELECT * FROM (
SELECT PARSING_USER_ID, EXECUTIONS, SORTS, COMMAND_TYPE,
DISK_READS, sql_text
FROM v$sqlarea
ORDER BY disk_reads DESC
) WHERE ROWNUM < 10;
SELECT se.sid, se.serial#, pr.SPID, se.username, se.status,
se.terminal, se.program, se.MODULE, se.sql_address,
st.event, st.p1text, si.physical_reads, si.block_changes
FROM v$session se, v$session_wait st, v$sess_io si, v$process pr
WHERE st.sid = se.sid
AND st.sid = si.sid
AND se.PADDR = pr.ADDR
AND se.sid > 6
AND st.wait_time = 0
AND st.event NOT LIKE '%SQL%'
ORDER BY physical_reads DESC;
掌握上述查詢語句,可覆蓋 Oracle SQL 監控的核心場景。建議根據實際環境調整過濾條件(如機器名、用戶、時間範圍),並結合 AWR/ASH 報告進行深度分析。若您有更高效的查詢方式,歡迎留言交流。