Oracle數據庫：鎖表查詢以及空間使用情況

1、有時候，項目突然崩潰，找不到原因，這時候可以去看看是不是鎖表了

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#;


--解鎖引號中'sid,serial'
ALTER system kill session '60,4111'; 

2、查看數據庫空間使用情況

wITH df AS
 (SELECT tablespace_name, round(SUM(bytes) / 1024 / 1024) totalspace
    FROM dba_data_files
   GROUP BY tablespace_name),
fs AS
 (SELECT tablespace_name, round(SUM(bytes) / 1024 / 1024) freespace
    FROM dba_free_space
   GROUP BY tablespace_name)
SELECT df.tablespace_name "Tablespace", (df.totalspace - nvl(fs.freespace, 0)) "Used MB",
       nvl(fs.freespace, 0) "Free MB", df.totalspace "Total MB",
       round(100 * (nvl(fs.freespace, 0) / df.totalspace)) "Pct. Free"
  FROM df
  LEFT OUTER JOIN fs
    ON (df.tablespace_name = fs.tablespace_name)
 WHERE df.tablespace_name = 'USERS';