The key methods are DataContext.SetEntityRefQueries() and DataContext.SetEntitySetsQueries()
They are called from DataContext._GetOrRegisterEntity(), called from DataContext.Register() which is called from QueryRunner.GetUniqueRow() and QueryRunner.Select(). I suppose that QueryRunner run queries: so it could be the starting point to work/study for implementing lazy loading. Giacomo On Tue, Apr 14, 2009 at 3:43 PM, Giacomo Tesio <[email protected]> wrote: > RTFM? What a BOFH! :-D > > > On Tue, Apr 14, 2009 at 3:41 PM, Pascal Craponne <[email protected]> wrote: > >> http://msdn.microsoft.com/en-us/library/bb341748.aspx >> http://msdn.microsoft.com/en-us/library/bb348960.aspx >> >> DbLinq API is similar to Linq2SQL API, so MSDN will provide you a lot of >> anwers. >> Never forget to RTFM :) >> >> Regarding the place where they are filled, you'll need to search by >> yourself, since we appear to have the same level of knowledge for this >> question (==none). >> >> On Tue, Apr 14, 2009 at 15:36, Giacomo Tesio <[email protected]> wrote: >> >>> Very good explaination. >>> >>> Some other question about this: >>> - What's the difference between EntitySet and EntityRef? >>> - Where are they filled/loaded? aka: where are the queries executed (i've >>> found no call to Load in the core code, just in tests) >>> >>> About the mutual references, I think that EntityTraker shoul be enought. >>> >>> After all, EntityTracking is a requirement even for Linq2Sql's lazy >>> loading... >>> >>> >>> Giacomo >>> >>> >>> On Tue, Apr 14, 2009 at 11:53 AM, Pascal Craponne <[email protected]>wrote: >>> >>>> Well, let's try :) >>>> 1. First of all, lazy loading means that after the first load, all >>>> entity's EntitySets and EntityRefs are empty. >>>> 2. The first time they're used, we want them to actually load the >>>> referenced entities and keep them for further reference. >>>> 3. Next, when using EntitySets and EntityRefs, we get a fast access to >>>> the referenced entities, because they're already loaded. >>>> >>>> Until here, I think we all agree. >>>> >>>> So now, let's see each point in details. >>>> We start from point 2, where the effective loading is done. >>>> The EntitySet or EntityRef needs: >>>> a. A foreign key referencing the entities to be loaded. >>>> b. A reference to the table >>>> c. A reference to the DataContext, or something like this. >>>> Once invoked when unitialized, the EntitySet/Ref just performs a request >>>> on the foreign keys to load the entities. >>>> >>>> Now let's move to point 1. >>>> When an entity is loaded for the first time, its EntitySets and Refs are >>>> initialized with the foreign keys and all necessary information to perform >>>> lazy loading. >>>> >>>> Point 3 is no problem at all. >>>> >>>> So our EntitySet/Ref can be initialized in two ways: >>>> - providing the entities (to allow eager loading, or current system). >>>> - providing the foreign keys and all required information. >>>> >>>> But, of course, this would be too simple, since there are a few problems >>>> to handle: >>>> - mutual reference: an entity referenced with an EntitySet also has an >>>> EntityRef to its referencing entity (am I clear?). We need to be sure that >>>> all links are correct. This should probably work without any change thanks >>>> to the cache. >>>> - correct use of cache (Giacomo, I know you are fully concerned with >>>> this :). This should work correctly if we reuse the DataContext. >>>> - DataContext lifetime. When using lazy loading, we imply that the >>>> DataContext is keep somewhere, so we may change its lifetime when used in a >>>> service architecture. Worse, we could get problems when the DataContext >>>> connection is closed. This is usually why lazy loading isn't allowed from >>>> outside a service call, because the connection and transactions are closed, >>>> and lazy loading can not be performed anymore. >>>> >>>> There may be some other problems, but I dumped here all the ideas I had >>>> at the moment :) >>>> >>>> Pascal. >>>> >>>> On Tue, Apr 14, 2009 at 11:11, Giacomo Tesio <[email protected]> wrote: >>>> >>>>> Mmm... Do you know where I could work for implementing a correctly >>>>> working lazy loading? >>>>> >>>>> Yet I've no complexive view of the source code, so any input is >>>>> welcome. >>>>> >>>>> I saw Pablo worked on EntityRef and EntitySet but I've not yet idea of >>>>> the difference. >>>>> Could you explain me? >>>>> >>>>> >>>>> Giacomo >>>>> >>>>> >>>>> On Tue, Apr 14, 2009 at 10:59 AM, Pascal Craponne <[email protected]>wrote: >>>>> >>>>>> As far as I remember, it's neither eager or lazy.The linked entities >>>>>> are loaded after the requested one are processed, and this, recursively. >>>>>> >>>>>> This is not eager because there are multiple requests to get all the >>>>>> work done. >>>>>> This is not lazy because when items are loaded all subsequent entities >>>>>> are also loaded. >>>>>> >>>>>> Pablo implemented this, but he's not very active on the list by these >>>>>> days :S >>>>>> >>>>>> On Mon, Apr 13, 2009 at 23:21, Giacomo Tesio <[email protected]>wrote: >>>>>> >>>>>>> Reading >>>>>>> >>>>>>> http://groups.google.com/group/dblinq/browse_thread/thread/283191499b74199f >>>>>>> and >>>>>>> >>>>>>> http://groups.google.it/group/dblinq/browse_thread/thread/4a67b172b607b0f9/666ae4667594c828?hl=it&lnk=gst&q=lazy+load# >>>>>>> >>>>>>> I could not understand if DbLinq currently support lazy loading or >>>>>>> not... >>>>>>> >>>>>>> Can you help me? >>>>>>> >>>>>>> >>>>>>> Giacomo >>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> >>>> >>>> >>>> >>> >>> >>> >> >> >> >> > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "DbLinq" group. 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