For those interested by a SQL-only sudoku solver, here's a 3 part (in French but Google Translate does a fair job of translating it to English) article on the subject.
http://endormitoire.wordpress.com/2012/ ... re-partie/
http://endormitoire.wordpress.com/2012/ ... me-partie/
http://endormitoire.wordpress.com/2013/ ... me-partie/
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