harmful statistics in DB13

[Former Member]

Hi Friends,

Whats that mean if we get warning in Check db job that there are harmful statistics for some tables and indexes. I browse thru some of the threads before posting and I could able to get the solution but I want to know what if these harmful statistics exist in the database without being taken care and what happen if we delete these harmful statistics will it effect the performance of database for a good or bad ?

Thank you

Mandra

[former_member197466]

Hi Mandra,

SAP note 435290 point 22 talked about the HARMFUL_STATISTICS in details.

The HARMFUL_STATISTICS on indexes could be caused by the active status

on the corresponding tables set to N in DBSTATC.

You can reinitial the DBSTATC using the script dbstatc<db_version>.sql as per SAP note 40370

It is advisable to run the script as per SAP note 1020260 to create the statistics delivered by SAP for special tables.

Remarks:

If you have maintained the DBSTATC table manually, you need to make the changes again.

Cheers,

Ivy

[former_member204080]

Hi,

There are some tables which schould not have statitistics since those statistics can affect DB performance .

If u want to delete u can use

brconnect -u / -c -f stats u2013t harmful u2013d

Please go through this guide

http://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/6b8d972f-0d01-0010-f281-b8178703f...

[volker_borowski2]

Ignore my comment, if you still run Oracle 9!

There are some tables which schould  not have statitistics since those statistics can affect DB performance .

This advice is outdated since Oracle 10!

Since Oracle 10 ALL tables, even Cluster Tables should have statistics.

Probably in your Upgrade someone forgot to update the corresponding check tables.

Work out Note 403704, choose the correct scripts for your DB release and apply them.

Volker