On Demand Block Level Recovery 2

[NJCommutr]

Our software vendor followed up with Oracle on an ORA-600 internal code error. The fix we were given was to shutdown the database and edit init.ora, adding the statement enable_block_level_transaction_recovery=FALSE, then restart the database. They said that this turns off a feature called "on demand block level recovery." I would prefer to read the documentation first, but I cannot find any mention of this feature or that initialization parameter. Can anybody tell me where to find this in the 8.1.7 documentation?

Thank you,

Michael

 

[sem]

This is so-called hidden parameter. Normally they're not documented and shouldn't be changed unless instructed by Oracle Support.

Regards, Dima

 

[NJCommutr]

Dima,

Thank you for the information. I didn't know that there were hidden parameters, so I have learned something new.

Regards,

Michael

 

[sem]

Normally all parameters starting from underscore are hidden. The "less hidden" of them is _system_trig_enabled, that may be used during manual java installation. You may list all hidden parameters (or at least AFAIK all) by

select i.ksppinm, v.ksppstvl, v.ksppstdf, i.ksppdesc
from x$ksppi i, x$ksppcv v
where v.indx=i.indx
and substr(ksppinm,1,1)='_'
order by ksppinm

Though, again, don't change them withough Support, because besides their main meaning they may cause some side effects.

Regards, Dima

 

[NJCommutr]

Dima,

I am glad you mentioned that the parameters start from underscore. That's how it appeared in the e-mail I received from our software vendor, and I thought it was a typo.

Is there a setup script that needs to be run to generate the views that you mentioned? I tried to desc the views, substituting v$, dba_ , or user_ for the x, as well as trying to desc x$ksppi; but they cannot be found.

Thank you,

Michael

 

[sybaseguru]

Michael,

You need "sys" user privileges to see the hidden parameeters. There are in excess of 500 of these. The parameter you are interested shows:

 sys@MYDB.WORLD> select i.ksppinm, v.ksppstvl, v.ksppstdf, i.ksppdesc
  2   from x$ksppi i, x$ksppcv v
  3   where v.indx=i.indx
  4  and ksppinm like '%enable_block_level%'
  5  /

KSPPINM
----------------------------------------------------------------
KSPPSTVL
------------------------------------------------------------------------------------------------------------------------------------
KSPPSTDF  KSPPDESC
--------- ----------------------------------------------------------------
_enable_block_level_transaction_recovery
TRUE
TRUE      enable block level recovery

good luck

 

[NJCommutr]

That worked for me !!!

Thank you.