9、查看数据库的创建日期和归档方式
Select Created, Log_Mode, Log_Mode From V$Database;
10、捕捉运行很久的SQL
column username format a12
column opname format a16
column progress format a8
select username,sid,opname,
round(sofar*100 / totalwork,0) '%' as progress,
time_remaining,sql_text
from v$session_longops , v$sql
where time_remaining <> 0
and sql_address = address
and sql_hash_value = hash_value
/
11、查看数据表的参数信息
SELECT partition_name, high_value, high_value_length, tablespace_name,
pct_free, pct_used, ini_trans, max_trans, initial_extent,
next_extent, min_extent, max_extent, pct_increase, FREELISTS,
freelist_groups, LOGGING, BUFFER_POOL, num_rows, blocks,
empty_blocks, avg_space, chain_cnt, avg_row_len, sample_size,
last_analyzed
FROM dba_tab_partitions
--WHERE table_name = :tname AND table_owner = :towner
ORDER BY partition_position
12、查看还没提交的事务
select * from v$locked_object;
select * from v$transaction;
13、查找object为哪些进程所用
select
p.spid,
s.sid,
s.serial# serial_num,
s.username user_name,
a.type object_type,
s.osuser os_user_name,
a.owner,
a.object object_name,
decode(sign(48 - command),
1,
to_char(command), 'Action Code #' to_char(command) ) action,
p.program oracle_process,
s.terminal terminal,
s.program program,
s.status session_status
from v$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='SUBSCRIBER_ATTR'
order by s.username, s.osuser
14、回滚段查看
select rownum, sys.dba_rollback_segs.segment_name Name, v$rollstat.extents
Extents, v$rollstat.rssize Size_in_Bytes, v$rollstat.xacts XActs,
v$rollstat.gets Gets, v$rollstat.waits Waits, v$rollstat.writes Writes,
sys.dba_rollback_segs.status status from v$rollstat, sys.dba_rollback_segs,
v$rollname where v$rollname.name(+) = sys.dba_rollback_segs.segment_name and
v$rollstat.usn (+) = v$rollname.usn order by rownum
15、耗资源的进程（top session）
select s.schemaname schema_name, decode(sign(48 - command), 1,
to_char(command), 'Action Code #' to_char(command) ) action, status
session_status, s.osuser os_user_name, s.sid, p.spid , s.serial# serial_num,
nvl(s.username, '[Oracle process]') user_name, s.terminal terminal,
s.program program, st.value criteria_value from v$sesstat st, v$session s , v$processp
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
ORACLE日志路径：/export/home/oracle/admin/cqwlzc/bdump/alert_cqwlzc.log为当前日志
几个特实用的函数
ASCII
返回与指定的字符对应的十进制数;
SQL> select ascii(A) A,ascii(a) a,ascii(0) zero,ascii( ) space from dual; A A ZERO SPACE
--------- --------- --------- --------- 65 97 48 32
2. CHR
给出整数,返回对应的字符;
SQL> select chr(54740) zhao,chr(65) chr65 from dual; ZH C -- - 赵 A 3. CONCAT 连接两个字符串;
SQL> select concat(010-,88888888)||转23 高乾竞电话 from dual; 高乾竞电话 ---------------- 010-88888888转23 4. INITCAP
返回字符串并将字符串的第一个字母变为大写; SQL> select initcap(smith) upp from dual; UPP -----
Smith
5.INSTR(C1,C2,I,J)
在一个字符串中搜索指定的字符,返回发现指定的字符的位置; C1 被搜索的字符串 C2 希望搜索的字符串 I 搜索的开始位置,默认为1 J 出现的位置,默认为1
SQL> select instr(oracle traning,ra,1,2) instring from dual; INSTRING --------- 9
6.LENGTH 返回字符串的长度;
SQL> select name,length(name),addr,length(addr),sal,length(to_char(sal)) from gao.nchar_tst; NAME LENGTH(NAME) ADDR LENGTH(ADDR) SAL LENGTH(TO_CHAR(SAL)) ------ ------------ ---------------- ------------ --------- -------------------- 高乾竞 3 北京市海锭区 6 9999.99 7
7.LOWER
返回字符串,并将所有的字符小写
SQL> select lower(AaBbCcDd)AaBbCcDd from dual; AABBCCDD -------- aabbccdd
8.UPPER
返回字符串,并将所有的字符大写
SQL> select upper(AaBbCcDd) upper from dual; UPPER -------- AABBCCDD
9.RPAD和LPAD(粘贴字符) RPAD 在列的右边粘贴字符 LPAD 在列的左边粘贴字符
SQL> select lpad(rpad(gao,10,*),17,*)from dual; LPAD(RPAD(GAO,1 ----------------- *******gao******* 不够字符则用*来填满
10.LTRIM和RTRIM
LTRIM 删除左边出现的字符串 RTRIM 删除右边出现的字符串
SQL> select ltrim(rtrim( gao qian jing , ), ) from dual; LTRIM(RTRIM( ------------- gao qian jing