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Discussion on today's telcon

From: ashok malhotra <ashok.malhotra@oracle.com>
Date: Tue, 02 Feb 2010 15:05:59 -0800
Message-ID: <4B68AFD7.3020100@oracle.com>
To: Richard Cyganiak <richard@cyganiak.de>, public-xg-rdb2rdf <public-xg-rdb2rdf@w3.org>
Hi Richard:
I'm thinking about the discussion we had on the telcon this morning and 
I have a couple of questions.

Let us agree on the premise that MySQL does a poor job of optimizing SQL 
queries that contain
subqueries and that using such views would entail a serious performance hit.
You said that the R2RQ approach helps rewrite such queries in a form 
that is more performant.
Could you give us an example of how it does that?

Second, suppose we go with the SQL-View approach could we not add a 
Informative Note that
said "If you are using MySQL and your view has one or more subqueries in 
it then you may take
a performance hit.  We suggest that you rewrite the view in the 
following manner ..." 
Does that make sense?
-- 
All the best, Ashok
Received on Tuesday, 2 February 2010 23:07:00 GMT

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