to get a speed advantage from dbms_stats in parallel do you have to the tablespace 
and/or segments broken up over several mount points? 
> 
> From: "Jankovic, Djordje" <[EMAIL PROTECTED]>
> Date: 2003/06/02 Mon PM 02:34:41 EDT
> To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]>
> Subject: RE: Need help
> 
> I have done some test before and found out that analyze is faster than dbms_stats 
> for smaller tables only (less than 10M) - and the difference was not that big (for 
> example very small tables dbms_stats would do a compute instead of estimate).  For 
> large tables they are pretty much the same.  And this is comparing dbms_stats 
> working in serial mode.  You can do stuff in parallel which could change the picture 
> in dbms_stats favor. 
>  
> dbms_stats is more accurate (since its introduction incorrect statistics gathering 
> was discovered for ANALYZE), it supports better granularity control (partitions, 
> subpartitions).  Using dbms_stats you can also export and import statistics: save 
> the old statistics before the run and reuse the old statistics in case you don't 
> like the new ones.
>  
> There are a number of other advantages: treating stale tables, automatic estimate 
> sample size, collecting histogram info only for skewed columns (at least the ones 
> that oracle thinks are skewed).  Using dbms_stats you can also collect system stats.
>  
> And analyze is not depreciated in 9i.
>  
> AFAIK the only things dbms_stats does not do are: finding chained/migrated rows, 
> computing cluster statistics, and validating the structure.
>  
> Djordje
> 
> -----Original Message-----
> [mailto:[EMAIL PROTECTED]
> Sent: Monday, June 02, 2003 10:50 AM
> To: Multiple recipients of list ORACLE-L
> 
> 
> Hi all,
>          Can anyone tell me which of the following performs better in collecting 
> statistics of a table:
>  Analyze command   or
>  Dbms_stats.gather_table_stats
>  
>       I tried my queries with both the options -- but always Analyze is 
> out-performing the dbms_stats.
> But i read in a document that Dbms_stats performs better !!
> Besides I also read that Analyze command will be deprecated from Oracle 9i.
>  
>  So can anyone tell me why dbms_stats is performing poor...
>  Are there any paramters that need to be set to increase the performace of 
> dbms_stats ?
>  
> Thanks in advance.
>  
> Regards
> Kesh
>  
> 
> 
> 


I have done some test before and found out that analyze is faster than dbms_stats for smaller tables only (less than 10M) - and the difference was not that big (for example very small tables dbms_stats would do a compute instead of estimate).  For large tables they are pretty much the same.  And this is comparing dbms_stats working in serial mode.  You can do stuff in parallel which could change the picture in dbms_stats favor. 
 
dbms_stats is more accurate (since its introduction incorrect statistics gathering was discovered for ANALYZE), it supports better granularity control (partitions, subpartitions).  Using dbms_stats you can also export and import statistics: save the old statistics before the run and reuse the old statistics in case you don't like the new ones.
 
There are a number of other advantages: treating stale tables, automatic estimate sample size, collecting histogram info only for skewed columns (at least the ones that oracle thinks are skewed).  Using dbms_stats you can also collect system stats.
 
And analyze is not depreciated in 9i.
 
AFAIK the only things dbms_stats does not do are: finding chained/migrated rows, computing cluster statistics, and validating the structure.
 
Djordje
-----Original Message-----
From: Jayaram Keshava Murthy (Cognizant) [mailto:[EMAIL PROTECTED]
Sent: Monday, June 02, 2003 10:50 AM
To: Multiple recipients of list ORACLE-L
Subject: Need help

Hi all,
         Can anyone tell me which of the following performs better in collecting statistics of a table:
 Analyze command   or
 Dbms_stats.gather_table_stats
 
      I tried my queries with both the options -- but always Analyze is out-performing the dbms_stats.
But i read in a document that Dbms_stats performs better !!
Besides I also read that Analyze command will be deprecated from Oracle 9i.
 
 So can anyone tell me why dbms_stats is performing poor...
 Are there any paramters that need to be set to increase the performace of dbms_stats ?
 
Thanks in advance.
 
Regards
Kesh
 

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