Re: Any quick way to remove histograms?
- From: Wolfgang Breitling <breitliw@xxxxxxxxxxxxx>
- To: alberto.dellera@xxxxxxxxx
- Date: Fri, 16 Mar 2007 15:36:36 -0600
I also did a quick check and just using
exec
dbms_stats.set_column_stats(user,'table_name',colname=>'column_name',distcnt=>
<num_distinct>);
will remove the histogram without removing the low_value and high_value.
At 01:40 PM 3/16/2007, Alberto Dell'Era wrote:
On 3/16/07, Allen, Brandon <Brandon.Allen@xxxxxxxxxxx> wrote:
Is there any faster way to remove histograms other than re-analyzing the
table? I want to keep the existing table, index & column stats, but with
only 1 bucket (i.e. no histograms).
You might try the attached script, that reads the stats using
dbms_stats.get_column_stats and re-sets them, minus the
histogram, using dbms_stats.set_column_stats.
I haven't fully tested it - it's only 10 minutes old, even
if I have slightly modified for you another script I've used for
quite some time - and the spool on 10.2.0.3 seems to confirmthat
the histogram is, indeed, removed, while all the other statistics
are preserved. I have also reset density to 1/num_distinct, that
is the value you get if no histogram is collected.
Regards
Wolfgang Breitling
Centrex Consulting Corporation
www.centrexcc.com
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- References:
- Any quick way to remove histograms?
- From: Allen, Brandon
- Re: Any quick way to remove histograms?
- From: Alberto Dell'Era
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On 3/16/07, Allen, Brandon <Brandon.Allen@xxxxxxxxxxx> wrote:
Is there any faster way to remove histograms other than re-analyzing the table? I want to keep the existing table, index & column stats, but with only 1 bucket (i.e. no histograms).
You might try the attached script, that reads the stats using dbms_stats.get_column_stats and re-sets them, minus the histogram, using dbms_stats.set_column_stats. I haven't fully tested it - it's only 10 minutes old, even if I have slightly modified for you another script I've used for quite some time - and the spool on 10.2.0.3 seems to confirmthat the histogram is, indeed, removed, while all the other statistics are preserved. I have also reset density to 1/num_distinct, that is the value you get if no histogram is collected.
- Any quick way to remove histograms?
- From: Allen, Brandon
- Re: Any quick way to remove histograms?
- From: Alberto Dell'Era