查询存档

清除优化缓存
alter system flush shared_pool ;
alter system flush BUFFER_CACHE ;

缓存
sys.v_$db_object_cache

查询最近执行的sql
select * from v$sqlarea t where t.PARSING_SCHEMA_NAME in ('CPFAIX') order by t.LAST_ACTIVE_TIME desc;

查询连接数据库的用户相关信息
SELECT osuser,
       a.username,
       cpu_time  / 1000000 || 's',
       sql_fulltext,
       machine,b.*
  from v$session a, v$sqlarea b
 where a.sql_address = b.address
 order by cpu_time  desc;
 
select username,count(username) from v$session where username is not null group by username;

SELECT username, machine, program, status, COUNT(machine) AS 链接数
  FROM v$session
 GROUP BY username, machine, program, status
 ORDER BY machine;

查询数据库最大几张表及表大小
select a.*
    from(
      select owner,segment_name,SEGMENT_TYPE, round(bytes/1024/1024/1024,2) all_size
      from dba_segments
      where SEGMENT_TYPE='TABLE' and owner='CPFAIX'
      order by  all_size desc
     ) a where rownum <15;
--表大小
SELECT bytes/1024/1024 ||'MB' TABLE_SIZE ,u.* FROM USER_SEGMENTS U WHERE U.SEGMENT_NAME='SYS_EXCHANGELOG';

--表空间大小
SELECT SUM(BYTES) / 1024 / 1024/1024 ||'GB' FROM USER_SEGMENTS U  WHERE TABLESPACE_NAME = 'CPF';
 
 --所有表空间大小
 SELECT A.TABLESPACE_NAME,
        FILENUM,
        TOTAL "TOTAL (GB)",
        F.FREE "FREE (GB)",
        TO_CHAR(ROUND(FREE * 100 / TOTAL, 2), '990.00') "FREE%",
        TO_CHAR(ROUND((TOTAL - FREE) * 100 / TOTAL, 2), '990.00') "USED%",
        ROUND(MAXSIZES, 2) "MAX (GB)"
   FROM (SELECT TABLESPACE_NAME,
                COUNT(FILE_ID) FILENUM,
                SUM(BYTES / (1024 * 1024 * 1024)) TOTAL,
                SUM(MAXBYTES) / 1024 / 1024 / 1024 MAXSIZES
           FROM DBA_DATA_FILES
          GROUP BY TABLESPACE_NAME) A,
        (SELECT TABLESPACE_NAME,
                ROUND(SUM(BYTES / (1024 * 1024 * 1024))) FREE
           FROM DBA_FREE_SPACE
          GROUP BY TABLESPACE_NAME) F
  WHERE A.TABLESPACE_NAME = F.TABLESPACE_NAME;