oracle 查询表空间使用情况与查询有哪些数据库实例在运行

oracle 查询表空间使用情况与查询有哪些数据库实例在运行

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

　　

25. 查询表空间的碎片程度

select tablespace_name,count(tablespace_name) from dba_free_space group by tablespace_name

　　having count(tablespace_name)>10;

　　alter tablespace name coalesce;

　　alter table name deallocate unused;

　　create or replace view ts_blocks_v as

　　select tablespace_name,block_id,bytes,blocks,'free space' segment_name from dba_free_space

　　union all

　　select tablespace_name,block_id,bytes,blocks,segment_name from dba_extents;

　　select * from ts_blocks_v;

　　select tablespace_name,sum(bytes),max(bytes),count(block_id) from dba_free_space

　　group by tablespace_name;

　　

26。查询有哪些实例在运行

select inst_name from v$active_instances;

　　===========================================================

　　######### 创建数据库----look $ORACLE_HOME/rdbms/admin/buildall.sql #############

　　create database db01

　　maxlogfiles 10

　　maxdatafiles 1024

　　maxinstances 2

　　logfile

　　GROUP 1 ('/u01/oradata/db01/log_01_db01.rdo') SIZE 15M,

　　GROUP 2 ('/u01/oradata/db01/log_02_db01.rdo') SIZE 15M,

　　GROUP 3 ('/u01/oradata/db01/log_03_db01.rdo') SIZE 15M,

　　datafile 'u01/oradata/db01/system_01_db01.dbf') SIZE 100M,

　　undo tablespace UNDO

　　datafile '/u01/oradata/db01/undo_01_db01.dbf' SIZE 40M