[mapserver-users] MapServer Oracle performance

[Smith, Michael ERDC-CRREL-NH]

All,

This is true and I have a patch ready to address this and use bind variables
in maporaclespatial.c. Howard (hobu) has the patch and was going to evaluate
it and incorporate into trunk when he gets a chance.

I haven't seen an amazing boost in performance but it does reduce the amount
of duplicate sql in the SGA.

Mike


-- 
Michael Smith
RSGIS Center
US Army Corps of Engineers




On 8/27/09  3:07 PM, "Bart van den Eijnden (OSGIS)" <bartvde at osgis.nl>
wrote:

> Hi,
> 
> I think you're right. Do you have any idea of the possible performance
> impact?
> 
> For a workaround, how is your knowledge of the C language, maybe you can
> write a patch to maporaclespatial.c?
> 
> Best regards,
> Bart
> 
> micklesh wrote:
>> Hi everyone.
>> 
>> I did some research and found a strange thing. Hope I'm wrong, but...
>> 
>> It seems to me that when mapserver fetches data from the database, all
>> parameters for "where" clause of the query string (for example coordinates
>> for MDSYS.SDO_ORDINATE_ARRAY() procedure) are string literals and not
>> oracle's bind variables.
>> This forces the DB to "hard parse" every query from mapserver. But hard
>> parse of the query is very CPU intensive process, so data fetching is slower
>> than it could be.
>> Can anyone confirm this, and if so, is there a workaround of such a problem?
>> 
>> Regards, Michael
>>   
>