Re: DBA view slow

M Rothwell <ThisIsABadAddress_at_toobad.com> wrote:

>Ed Stevens wrote:
>
>> On Wed, 13 Oct 2004 14:53:48 -0700, M Rothwell
>> <ThisIsABadAddress_at_toobad.com> wrote:
>>
>>
>>>Oracle 9.2.0.4 on HP-UX
>>>
>>>I have a dev tool that runs a bunch of queries at start-up and when I'm
>>>monitoring the db.
>>>
>>>The following query can take several minutes to return.
>>>
>>>SELECT 1
>>> FROM SYS.DBA_EXTENTS
>>> WHERE ROWNUM = 1
>>>
>>>I tried to do an explain plan on it, but dont have the proper privs.
>>>The powers that be (corp DBA's) say that you shouldn't run stats on sys
>>>tables.
>>>
>>>I cant change the query, or add a hint because it's embedded in the
>>>tool. Is there anything I can have the DBA's do to make this query
>>>perform better. I cant even figure out why the tool is running this query.
>>>
>>>Thanks
>>>
>>>Michael
>>
>>
>> Just for grins, have you tried executing that query from SQL*Plus? If
>> the tool runs 'a bunch of queries' how do you know this single query
>> is the culprit?
>
>I captured all the SQL statements that were being run, then I ran each
>statement in SQL*Plus. This is the only statement that was slow. The
>others returned data quite quickly.
>
>I'll see if I can talk the DBA's into analyzing the table. I have my
>doubts, but it cant hurt to ask.
>
>Michael

Not a good idea..System tables should not be analyzed ( see Oracle Docs for reasons)

The overarching question is why in the h**l any application would run such a meaningless query?

( as an aside, it takes microseconds to run in our 9.2 database) Received on Thu Oct 14 2004 - 11:25:35 CDT