Forgot to mention, I have a project up on GitHub that is set up for checking the behavior of EF and Linq to SQL, also showing the generated SQL. It includes its own database, so it's ready to run tests out of the box.
https://github.com/patearl/NHibernate.Linq.Development I was dreaming of being able to compare to llblgen too, but I imagine that would be problematic due to licensing and such. In any case, I do hope Frans can share his insight on this topic. I didn't see anything on this particular issue in my search of his blogs. Patrick Earl On Sat, Apr 2, 2011 at 6:23 PM, Patrick Earl <[email protected]> wrote: > Hi Harald. > > I finally had more time to dig into things deeper this morning. > > I was reading your description and I came to the part about d.E.P != 1 > not being equivalent to !(d.E.P == 1). As you mention, this is a bit > odd. The implied "existence" clause that allows non-existent records > in the negated case doesn't really follow the typical SQL semantics > where negating a relationship still does not include null records. > > In any case, this led me to wonder how EF and Linq to SQL do it. > Turns out they use left outer joins everywhere (in fact, Linq to SQL > doesn't even optimize to inner joins for simple cases). The clauses > themselves are just written as-is, with no extra existence checks. > > I'd be quite curious how llblgen handles this as well, being a > significant Linq provider. Any thoughts from the ReMotion guys? > > My gut is hinting that outer joins with no existence clauses is > better, since it leads to smaller queries and sane results in most > cases. > > Looking forward to hearing people's thoughts. > > Patrick Earl > > On Wed, Mar 30, 2011 at 3:44 PM, Harald Mueller <[email protected]> > wrote: >> Hi Patrick, all - >> >> I have now, to my best knowledge, added the final version of code handling >> the || and ! operators correctly to the NH-2583 issue. I added a patch file >> (NH-2583e.diff) as well as the rationale-and-design document >> LogicalOperatorsInNHibernateLinq.txt which tries to explain everything from >> meta-considerations down to the code level. >> >> There are now 74 tests which should provide a thorough coverage of the new >> code; and all (now) 3353 tests are still green. >> >> Feel free to discuss...! >> >> Best regards >> Harald >> >> >> -- >> GMX DSL Doppel-Flat ab 19,99 Euro/mtl.! Jetzt mit >> gratis Handy-Flat! http://portal.gmx.net/de/go/dsl >> >
