- From: Juan Sequeda <juanfederico@gmail.com>
- Date: Tue, 9 Feb 2010 03:06:02 -0600
- To: public-rdb2rdf-wg@w3.org
Received on Tuesday, 9 February 2010 09:06:30 UTC
Hi everybody, I updated the GeneratedSQL page [1] and showed what Ultrawrap does when it translated SPARQL to SQL. If wanted, I could explain this during our telcon. I also quickly did the experiments on SQL Server that Richard showed last time on MySQL. For the trivial subquery, SQL Server is smart, and treats both queries exactly the same. For the example, SQL Server does not compile out self joins either. However, the overhead is just 1.5 times slower. My guess is that for other commercial databases, the results should be the same. Conclusion: MySQL does not have good optimization (I think we all knew that). [1] http://www.w3.org/2001/sw/rdb2rdf/wiki/GeneratedSQL Juan Sequeda +1-575-SEQ-UEDA www.juansequeda.com
Received on Tuesday, 9 February 2010 09:06:30 UTC