1：查看表空间的名称及大小
select t.tablespace_name, round(sum(bytes/(1024*1024)), 0) ts_size
from dba_tablespaces t, dba_data_files d
where t.tablespace_name = d.tablespace_name
group by t.tablespace_name
2：查看表空间物理文件名称及大小
select tablespace_name, file_id, file_name, round(bytes/(1024*1024), 0) total_space
from dba_data_files
3：查看回滚段名称及大小
select segment_name, tablespace_name, r.status, (initial_extent/1024) InitialExtent, (next_extent/1024) NextExtent, max_extents, v.curext CurExtent
from dba_rollback_segs r, v$rollstat v
where r.segment_id = v.usn(+)
order by segment_name;
4：查看控制文件
select * from v$controlfile;
5：查看日志文件
select * from v$logfile;
6：查看表空间使用情况
select sum(bytes) / (1024*1024) free_space, tablespace_name
from dba_free_space
group by tablespace_name; 表空间的剩余空间
select a.tablespace_name, a.bytes total, b.bytes used, c.bytes free, (b.bytes*100)/a.bytes "%used", (c.bytes*100)/a.bytes "%free"
from sys.sm$ts_avail a, sys.sm$ts_used b, sys.sm$ts_free c
where a.tablespace_name = b.tablespace_name and a.tablespace_name = c.tablespace_name
7：查看数据库对象
select owner, object_type, status, count(*) coutn#
from all_objects
group by owner, object_type ,status
8：查看数据库的版本
select *
from product_component_version;
9：查看数据库的创建日前和归档方式
select created, log_mode
from v$database;
10：捕捉运行很久的SQL
select username, sid, opname, round(sofar*100 / totalwork, 0) || '%' as progress, time_remaining, sql_text
from v$session_longops, v$sql
where time_remaining <>0
and sql_address = address
and sql_hash_value = hash_value
11：查看还没有提交的事务
select * from v$locked_object;
select * from v$transaction;
12：查看object为那些进程所用
select
p.spid,
s.sid,
s.serial# serial_num,
s.username user_name,
a.type object_type,
s.osuser os_user_name,
a.owner,
a.object object_name,
decode(sign(48 - command),
1,
to_char(command), 'Action Code #' || to_char(command) ) action,
p.program oracle_process,
s.terminal terminal,
s.program program,
s.status session_status
from v$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;
13：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$rollstat.waits, v$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$rollname.usn
order by rownum
14：查看SGA情况
select * from sys.v_$sgastat;
15：查看catched object
select owner, name, db_link, namespace, type, sharable_mem, loads, executions, locks, pins, kept
from v$db_object_cache
16：查询表空间使用情况
select a.tablespace_name "表空间名称",
100-round((nvl(b.bytes_free,0)/a.bytes_alloc)*100,2) "占用率(%)",
round(a.bytes_alloc/1024/1024,2) "容量(M)",
round(nvl(b.bytes_free,0)/1024/1024,2) "空闲(M)",
round((a.bytes_alloc-nvl(b.bytes_free,0))/1024/1024,2) "使用(M)",
Largest "最大扩展段(M)",
to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') "采样时间"
from (select f.tablespace_name,
sum(f.bytes) bytes_alloc,
sum(decode(f.autoextensible,'YES',f.maxbytes,'NO',f.bytes)) maxbytes
from dba_data_files f
group by tablespace_name) a,
(select f.tablespace_name,
sum(f.bytes) bytes_free
from dba_free_space f
group by tablespace_name) b,
(select round(max(ff.length)*16/1024,2) Largest,
ts.name tablespace_name
from sys.fet$ ff, sys.file$ tf,sys.ts$ ts
where ts.ts#=ff.ts# and ff.file#=tf.relfile# and ts.ts#=tf.ts#
group by ts.name, tf.blocks) c
where a.tablespace_name = b.tablespace_name and a.tablespace_name = c.tablespace_name
17：查询表空间碎片程度
select tablespace_name,sqrt(max(blocks)/sum(blocks))*
(100/sqrt(sqrt(count(blocks)))) FSFI
from dba_free_space
group by tablespace_name order by 1
