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<td class="text-paragraph-pattern-container mobile-resize-text " style="padding: 0px; border-collapse: collapse; padding: 0 0 10px 0; padding-top: 10px"> <span class="diffcontext">Attaching the discussion between Hardy and me on the subject<br /></span> <span class="diffaddedchars" style="background-color:#ddfade;">{noformat}</span> <span class="diffcontext"><br /></span> <span class="diffremovedchars" style="background-color:#ffe7e7;text-decoration:line-through;"><br /></span> <span class="diffcontext">11:14<br />emmanuel<br />ok the crux of the issue is about entities that have their @DocumentId which are not the JPa's @Id<br />hardy: if you look at returnAlreadyLoadedObjectsInCorrectOrder<br /><br />11:15<br />hardy<br />i see the FIXME<br /><br />11:15<br />emmanuel<br />the idea is that the objects do ahve been loaded<br />and we simply use the HashMap nature of Hibernate to retrieve them<br />But executeLoad does not do that int he case where @Id != @DocumentId<br />do you remember this code?<br /><br />11:16<br />hardy<br />it uses a Criteria<br /><br />11:16<br />emmanuel<br />right<br /><br />11:16<br />hardy<br />well, I remember partly. It was quite some time ago<br /><br />11:17<br />emmanuel<br />I think we should try and find a better approach somehow at some point<br /><br />11:17<br />hardy<br />for the @Id != @DocumentId case you mean?<br /><br />11:17<br />emmanuel<br />Maybe the first criteria query loads the object and project the docmentIdProperty and the entity<br /><br />11:17<br />hardy<br />or the whole apporach?<br /><br />11:17<br />emmanuel<br />and we keep this aroud<br />yes just for the @Id != @DocumentId<br />Today we literally do 1+ n queries <br />It's not super urgent but we cna't really say that we support this use case until we are somewhat close performance wise. Today it's a bit misleading and I fear people will learn it the hard way<br /><br />11:20<br />hardy<br />makes sense. we need to address this<br /><br />11:20<br />emmanuel<br />anyways, I wanted to know if you had an idea at the time on how to improve that<br /><br />11:21<br />hardy<br />not at the time<br />what do you mean with "Maybe the first criteria query loads the object and project the docmentIdProperty and the entity"<br /><br />11:22<br />emmanuel<br />The key is that we want the object by documentId value<br />if we do have that we don't have to do the criteria query again just to order the objects<br />so imagine it's a user with id and a ssn<br />the ssn is the @DocumentId<br />if the first criteria query returns rows that looks like <br />{ ssn1, person1 }<br />we have the data in memory<br />and we don't need the other criteria queries<br />makes sense?<br /><br />11:24<br />hardy<br />i see where you are going with that<br />an other thing we could try is to tackle the 1 + n problem, by not loading each entity with a separate query<br /><br />11:26<br />emmanuel<br />hardy: that's what my proposal aims at<br /><br />11:26<br />hardy<br />right<br /><br />11:26<br />emmanuel<br />the first query is a criteria query that does where 'ssn in (:listOfSSns)'<br />the n other queries are ssn = :ssn<br />but if we have the ssn, entity tuple in memory from the first query<br />we eliminate the n other queries altogether</span> <span class="diffaddedchars" style="background-color:#ddfade;"><br />{noformat}</span>
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