Re: Burned by DBMS_STATS **AGAIN**

I've just checked on my 8.1.7.4

create table t1 (n1 number, v1 varchar2(10)); create index t1_idx on t1(n1);

insert into t1
select rownum rownum
from all_objects
where rownum <= 100;

analyze table T1 compute statistics;

select * from user_tab_histograms
where table_name = 'T1';

This gives me two rows each
for N1 and V1.

Similarly

select low_value, high_value
from user_tab_columns
where table_name = 'T1';

gives me one row for each column,
with the high and low value set.

analyze table XXX compute statistics;

should be the equivalent of

    'for table for ALL columns size 1';

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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  who can answer the questions, but the
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The Co-operative Oracle Users' FAQ
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• Original Message ----- To: "Multiple recipients of list ORACLE-L" <ORACLE-L_at_fatcity.com> Sent: 08 April 2003 17:14

> OK, I've saved the histograms generated by each method using:
>
>
> Sure enough, the query returns no rows, leading me to believe that
ANALYZE
> TABLE...COMPUTE STATISTICS generates histograms of SIZE 1 for all
> NON-indexed columns. Does this conclusion sound correct? If so,
then it
> doesn't appear from the 8i docs that there is a method in DBMS_STATS
to
> emulate this. So, now what? I'm a little hesitant to initially
gather
> stats using ANALYZE, then rely on DBMS_STATS afterwards because of
the
> differences in the stats they gather. It would seem to me that
there's a
> very good chance that the stats that aren't regularly updated with
> DBMS_STATS will become stale and at some point could negatively
alter
> explain plans.
>

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

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