hibernate - JPA Left Join and Count -


i want retrieve foo objects , every foo object number of associated bar objects (zero or more) database. want in one single query , don't want fetch lists of bar objects sizes.

the following works, returns foo objects have matching bar objects:

@namedquery(name = "foo.findandcountbars", query = "     select new com.test.myresultcontainer(f, count(b.id))     foo f, bar b     f.uniquekey = b.uniquekey     group f.id ")

notice foo , bar not connected via primary keys. following want achieve (without explicit relationship such @onetomany in foo):

@namedquery(name = "foo.findandcountbars", query = "     select new com.test.myresultcontainer(f, count(b.id))     foo f left join bar b     on f.uniquekey = b.uniquekey     group f.id ")

i tried different syntax variations, eclipse tells me b.id unknown because bar not in from clause. how can this?


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