setMaxResult(0) should return an empty List
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Steve EbersoleDecember 7, 2016 at 6:48 PM
I dont not understand at all your statement "people request for 0 element to get the total elements count only without element". What do you mean by that?
Anyway we all agreed that setMaxRows(0) should mean to implicitly return an empty list immediately. Hibernate and JPA both define ways to define "no limit" to a Query. JPA defines setting it to the magic value java.lang.Integer#MAX_VALUE}. Hibernate supports that as a JPA provider, but we also support (and have supported) more "sane" imo ways to specify that. In terms of {{int values as defined by the spec we also recognize any negative integers (-1, etc) as meaning no rows. The Hibernate Query API also exposes this as an Integer, so another option there is to set it to {{null}.
alexis gayteDecember 3, 2016 at 5:53 PMEdited
in my specific case we send 2 requests :
one for the content
one for the total count of elements
Just to clarify a bit more,
people request for 0 element to get the total elements count only without element.
As the content is flagged as read if we fetch them.
So in this case the query return an empty list.
Thanks,
Alexis
Steve EbersoleDecember 3, 2016 at 3:52 PM
I set the fix version to 5.2.6 mainly to define an end-date to the decision here. Either we do "something", or we reject this. Of course what "something" is ends up being part of that decision.
Steve EbersoleDecember 3, 2016 at 3:51 PM
IMO Query#setMaxResults(0) "doesnt look logical at all"
So is the request here to have maxResults==0 be a trigger for Hibernate to immediately return Collections#emptyList?
alexis gayteNovember 29, 2016 at 11:16 AMEdited
my specific case is pagination as well,
one guy requests the end point to get the 'count only' with number of element 0. Which looks logical, but it ends up that he's never got the response from the server.
I think the most important problem on this issue, is the fact that we do not have the possibility to send a query with 'limit 0'. - if that is an sql specification -
As I said I fixed it from my side. The reason why I raised the ticket, it just doesnt look logical at all.
right now when we use setMaxResult(0), hibernate return all elements, as the sql instruction "limit" is not used.
We have this direct problem when we use a pagination and setMaxResult is can be set at 0.
That is link to "AbstractQueryImpl" and "LimitHelper".
the workaround is if "limit 0" is SQL correct we should accept it
if it isn't we should throw an exception.
But in any case we should create a request that return everything.
https://github.com/alexisgayte/hibernate-test-case-maxResult-0