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From Rick Hillegas <rick.hille...@oracle.com>
Subject Re: What should the "Graphical Query Explainer" shows?
Date Tue, 01 Jun 2010 13:23:44 GMT
Nirmal Fernando wrote:
> Hi Rick,
>
>   
>> I would also like to see the following information pop out. It is hard to
>> figure this out from the current query plans:
>>
>> 1) For scan nodes, what pieces of the WHERE clause were pushed into the
>> Store. I believe these turn up in the current query plans as "scan
>> qualifiers" and "next qualifiers".
>>     
>
> These are Varchar variables with a maximum length of 1024 characters.
> So adding these
> might take large space. Will it reduce the "graphical behavior" of the
> tool (since lot of text)?
>
> Thanks.
>
>   
Hi Nirmal,

I think that the xml form should be as rich as possible, conveying all 
of the information which is in the XPLAIN output. It is up to the 
visualizer to filter that information and to figure out what information 
should appear when. I don't know what you have in mind for 
visualization, but I think that the visualizer ought to be at least as 
capable as what I can do in Firefox today: I can collapse and expand xml 
nodes in order to hide noise and focus on the interesting information. 
What information is considered interesting will depend on the particular 
query and problem being debugged.

Thanks,
-Rick

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