Re: question about v$segment_statistics

"stephan11" <Stephan11_at_gmx.de> wrote in message news:1132698839.202200.250030_at_g14g2000cwa.googlegroups.com...
>i am using the 10g database . if i want statistic information about
> tables ( e.g how often a certain table is selected ) i have to use the
> view 'v$segment_statistics' . is this right ?
> if i enter the statement :
> select distinct owner from v$segment_statistics;
> the result of the query is :
>
> OWNER
> ------
> DBSNMP
> IX
> MDSYS
> SYS
> SYSMAN
> SYSTEM
> WKSYS
> WMSYS
> XDB
>
> why for example does not appear the user HR ?
>
> what do i have to do to get the statistic information from the table
> 'countries' of the user hr ?
>
> greeting s. f.
>

It looks like no-one has been querying the HR objects.

Warning - for general use, it is better to look at v$segstat to find hot spots, then use the object_id and data_object_id to identify the interesting objects.

v$segment_statistics is a based on a join between a very large memory structure and two or three data dictionary objects. Queries against it are not cheap on a large system.

-- 
Regards

Jonathan Lewis

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