Query Varie

Controllo Allocazione Spazio

Questa query controlla lo spazio allocato, e lo confronta con lo spazio di massima crescita dei datafiles. Utile per evidenziare casi in cui è necessario aggiungere altri datafiles.

select TBS.MB_MAX,
       TBS.MB_TBS,
       SEG.MB_SEG,
       TBS.MB_MAX-SEG.MB_SEG MB_FREE,
       TBS.TABLESPACE_NAME
  from (select round(sum(f.maxbytes)/(1024*1024)) MB_MAX,
               round(sum(f.user_bytes)/(1024*1024)) MB_TBS,
               f.tablespace_name TABLESPACE_NAME
          from dba_data_files f
         group by f.tablespace_name) TBS,
       (select round(sum(s.bytes)/(1024*1024)) MB_SEG,
               s.tablespace_name TABLESPACE_NAME
          from dba_segments s
         group by s.tablespace_name) SEG
 where SEG.tablespace_name=TBS.tablespace_name;

Shrink datafiles

set linesize 1000 pagesize 0 feedback off trimspool on
with
 hwm as (
  -- get highest block id from each datafiles ( from x$ktfbue as we don't need all joins from dba_extents )
  select /*+ materialize */ ktfbuesegtsn ts#,ktfbuefno relative_fno,max(ktfbuebno+ktfbueblks-1) hwm_blocks
  from sys.x$ktfbue group by ktfbuefno,ktfbuesegtsn
 ),
 hwmts as (
  -- join ts# with tablespace_name
  select name tablespace_name,relative_fno,hwm_blocks
  from hwm join v$tablespace using(ts#)
 ),
 hwmdf as (
  -- join with datafiles, put 5M minimum for datafiles with no extents
  select file_name,nvl(hwm_blocks*(bytes/blocks),5*1024*1024)
hwm_bytes,bytes,autoextensible,maxbytes
  from hwmts right join dba_data_files using(tablespace_name,relative_fno)
 )
select
 case when autoextensible='YES' and maxbytes>=bytes
 then -- we generate resize statements only if autoextensible can grow back to current size
  '/* reclaim '||to_char(ceil((bytes-hwm_bytes)/1024/1024),999999)
   ||'M from '||to_char(ceil(bytes/1024/1024),999999)||'M */ '
   ||'alter database datafile '''||file_name||''' resize '||ceil(hwm_bytes/1024/1024)||'M;'
 else -- generate only a comment when autoextensible is off
  '/* reclaim '||to_char(ceil((bytes-hwm_bytes)/1024/1024),999999)
   ||'M from '||to_char(ceil(bytes/1024/1024),999999)
   ||'M after setting autoextensible maxsize higher than current size for file '
   || file_name||' */'
 end SQL
from hwmdf
where
 bytes-hwm_bytes>1024*1024 -- resize only if at least 1MB can be reclaimed
order by bytes-hwm_bytes desc
/