Thanks, Fabio. That's an interesting blog post, I will check out the tolerant cache.
Could you explain a little why you don't think it is worth trying to update a query in the cache? I am thinking of the following tow situations: A) Current Situation: 1) do expensive query on table FOO, (NH mapping class FOO_ENTITY) and put query and entities returned in L2 cache 2) create new FOO_ENTITY 3) FOO_ENTITY is now cached in the entity cache 4) run query again: must hit RDBMS again OR B) With Query Updates: 1) do expensive query on table FOO, (NH mapping class FOO_ENTITY) and put query and entities returned in L2 cache 2) create new FOO_ENTITY 3) FOO_ENTITY is now cached in the entity cache 4) do not invalidate the query, but instead run in-memory query on FOO_ENTITY, and possibly add to cached query ids 5) no extra hit to RDBMS My NH knowledge is very limited, so I am probably missing something big here. Cheers, Jorge > you will not gain something querying first the cacje and then the RDBMS > where needed. > If you can accept "eventual consistency" queries avoiding the cache > invalidation at each insert/update/delete what you are looking for > is:http://fabiomaulo.blogspot.com/2009/04/tuning-nhibernate-tolerant-que... > > > > On Wed, Nov 17, 2010 at 12:45 PM, Throckmorton <[email protected]> wrote: > > Thanks, Stefan. Will see what I can cook up. > > But I am guessing that once you have the AST, it would be fairly > > easy to generate the LINQ query. And, since Mono has implemented > > LINQ, there may be some code I can scavenge there. > > > If this were possible, then one could really put the L2 query cache > > on drugs: not only cache the query results, but also the LINQ > > equivalent > > of the HQL, so that the LINQ query could be *run on the entity cache*. > > > Which would mean that after an insert, the query could be updated > > rather than > > invalidated, as it is currently done. > > > On Nov 17, 3:52 am, Stefan Wenig <[email protected]> wrote: > > > I was just going off on a tangent. AFAIK, what you describe cannot be > > > done, unless somebody comes and builds it. Wouldn't hold my breath > > > though, HQL was not built for in-memory execution. > > > > I'd rather go look for a way to serialize in-memory LINQ queries. > > > >http://stackoverflow.com/questions/4036489/what-is-the-easiest-way-to... > > > > Also, Silverlight RIA toolkit has code that does that. For remote > > > invocation, not storage, but hey... > > > problems: > > > - in RIA toolkit, serialization (client) and deserialization (server) > > > use similar, but different types. > > > - if you compile an IQueryable expression, it will compile to the > > > IQueryable and Queryable extension methods. you'd need to replace that > > > with IEnumerable and Enumerable extension methods so that they > > > actually do the work instead of just creating expression trees again. > > > > Other stuff might be available. Tell us if you find a way! > > > > HTH, > > > Stefan > > > > On 16 Nov., 21:12, Throckmorton <[email protected]> wrote: > > > > > Wait a second, I'm confused. > > > > > a) I start with an HQL query, which is just a string. > > > > b) NH is designed to apply this HQL to a database, by first converting > > > > to ANTLR > > > > c) I want to apply the HQL to an in-memory collection instead > > > > d) so, I could use the LINQ equivalent, if it can be generated from > > > > the HQL > > > > e) since LINQ and HQL get converted to ANTLR expression, I would need > > > > > HQL ==> ANTLR ===> LINQ > > > > > f) this may be currently impossible > > > > > On Nov 16, 11:12 am, Stefan Wenig <[email protected]> wrote: > > > > > > You're right, I skipped a step. I once asked steve strong whether he > > > > > could emit the HQL as a string for diagnostics. He said: easily. > > (much > > > > > easier than serializing and deserializing LINQ in any case...) > > > > > > but anyway, I digress. > > > > > > On 15 Nov., 11:55, Stefan Wenig <[email protected]> wrote: > > > > > > > BTW, internally, LINQ is converted to HQL. There might be a way to > > > > > > extract, save and execute this HQL. > > > > > > > On 13 Nov., 20:06, Jorge <[email protected]> wrote: > > > > > > > > yeah, I guess I will store a linq query along with the HQL. > > > > > > > Problem is, LINQ cannot be serialized to disk, while HQL can. > > > > > > > So, if HQL could be converted to LINQ, then this would be the > > nicest > > > > > > > solution. > > > > > > > > On Nov 13, 8:09 am, Jason Meckley <[email protected]> > > wrote: > > > > > > > > > that would be linq then :) > > > > > > > > > On Nov 12, 8:22 pm, Jorge <[email protected]> wrote: > > > > > > > > > > Hello! > > > > > > > > > Is it possible to take an HQL query and apply it to a > > collection of > > > > > > > > > entities in memory? > > > > > > > > > Something similar to LINQ? > > > > > > > > > > Thanks! > > > > > > > > > Jorge- Zitierten Text ausblenden - > > > > > > > > - Zitierten Text anzeigen -- Zitierten Text ausblenden - > > > > > > > - Zitierten Text anzeigen -- Zitierten Text ausblenden - > > > > > - Zitierten Text anzeigen - > > > -- > > You received this message because you are subscribed to the Google Groups > > "nhusers" group. > > To post to this group, send email to [email protected]. > > To unsubscribe from this group, send email to > > [email protected]<nhusers%[email protected]> > > . > > For more options, visit this group at > >http://groups.google.com/group/nhusers?hl=en. > > -- > Fabio Maulo -- You received this message because you are subscribed to the Google Groups "nhusers" group. 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