sql - HQL: using elements() on objects -

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say have database 2 tables: classes , students. each table contains metadata relevant topic. example, classes contains fields 'classid', 'name' , 'room_number' , students contains fields 'name', 'classid', 'age' , 'height' (say student can in 1 class).

what if want write hql query me classes include students names 'joe', 'bob', , 'fred'? if students contained 'classid' , 'name' think write following in hql.

from classes class   'joe' in elements(class.students) ,   'bob' in elements(class.students) ,   'fred' in elements(class.students)

however, students object in case. need perform joins explicitly?

from classes class   join class.students s1   join class.students s2   join class.students s2   s1.name = 'joe'   s2.name = 'bob'   s3.name = 'fred'

i imagine using 'fred' in elements performs these joins, more compact write! or there better way of doing altogether?

use sub-select:

from classes c  c.classid in(       select s.classid students s s.name in('joe', 'bob', 'fred')    )

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