Re: Re: Used size of a datafile.
- From: "biti_rainy" <biti_rainy@xxxxxxxxx>
- To: "jhn.aida@xxxxxx" <jhn.aida@xxxxxx>, "jkstill@xxxxxxxxx" <jkstill@xxxxxxxxx>
- Date: Sun, 9 Jan 2005 21:21:24 +0800
hi,Jesper Haure Norrevang
OS file is one oracle blocks bigger than oracle files .
2k/4k/8k/16k blocks LMT datafile has 8 oracle blocks oracle file header
and bitmap .
there is difference for dba_extents and (dba_data_files - dba_free_space)
and please notice the left space with a datafile that less than min
extent.
anyway,i think all that is not important.
Best regards
msn: biti_rainy@xxxxxxxxxxx
a dba from alibaba(china)
---- from the mail-----
>Thanks Jared,
>
>I think you have a good point here.
>I don't like when ad hoc SQL made by
>the DBA shows up as the most resource
>consuming statements in the database.
>I admit that my statement do not perform
>well.
>
>It reminds me, that the sum of bytes
>in DBA_FREE_SPACE and DBA_EXTENTS for
>a tablespace do not match the actual
>size of the datafiles. The difference is:
>- 1 block file header,
>- 1 block HEADER of bitmap used with locally
> managed tablespaces (LMT).
>- 6 blocks (may be more?) of LMT-bitmaps.
>
>The difference can be seen in
>DBA_DATA_FILES as the difference between
>USER_BYTES and BYTES.
>
>Regards
>Jesper Haure Norrevang
>
>
>----- Original Message -----
>From: Jared Still <jkstill@xxxxxxxxx>
>Date: Saturday, January 8, 2005 8:09 pm
>Subject: Re: Used size of a datafile.
>
>> You may consider using DBA_FREE_SPACE rather than DBA_EXTENTS.
>>
>> If there are a lot of objects in your database, it may be
>> (possibly much) less
>> expensive to query DBA_FREE_SPACE.
>>
>> On Sat, 08 Jan 2005 11:15:32 +0100, Jesper Haure Norrevang
>> <jhn.aida@xxxxxx> wrote:
>> > Vinod,
>> >
>> > select
>> > f.tablespace_name,
>> > f.file_name,
>> > sum(e.bytes) / 1024 / 1024 MB
>> > from dba_extents e, dba_data_files f
>> > where e.file_id = f.file_id
>> > group by f.tablespace_name, f.file_name
>> > order by f.tablespace_name, f.file_name;
>> >
>>
>>
>> --
>> Jared Still
>> Certifiable Oracle DBA and Part Time Perl Evangelist
>> --
>> //www.freelists.org/webpage/oracle-l
>>
>
>--
>//www.freelists.org/webpage/oracle-l
>
--
//www.freelists.org/webpage/oracle-l
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