java - JPA/Hibernate how to get N items of each category -



java - JPA/Hibernate how to get N items of each category -

let's assume have next auto entity in database: id, name, model.

i want retrieve n cars of each model. brevity sake, if have next models: bmw, porche, volkswagen, want 2 bmw, 2 porche, , 2 volkswagen.

is achievable through either single hql or sql query ?

the best i've achieved far using 3 separate queries each model.

not directly, no.

even plain sql have utilize union accomplish , not supported in hql.

what create view (for union) , map auto entity.

http://timezra.blogspot.de/2009/05/mapping-hibernate-entities-to-views.html

java mysql sql hibernate hql

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