现有学员张三，李四，ID分别为1和2； 求HQL语句查询：所有同时教了张三和李四的老师集合。 FROM Teachar ... 后面条件怎么写- -？求大神赐教...
public class Teachar{ private int id; private String name; private Set<Relation> relations = new HashSet<Relation>(0); }
public class Student{ private int id; private String name; private Set<Relation> relations = new HashSet<Relation>(0); }
public class Relation{ private int id; private Teachar teachar; private Student student; private int state; private ... }
[最优解释]
那就继续and r.teacher.id in(查出教王五的老师id) and r.teacher.id in(查出赵六的老师id).... 因为你这个需求是要取他们的交集就是都要存在。 [其他解释]
select b.teachar from Relation b where b.teachar.id in ((select a.teachar.id from Relation a where a.student.id=1)) and b.student.id=2;
[其他解释] from Teacher t where t.id in(select r.teacher.id from Relation r where r.student.id=1 or r.student.id=2); [其他解释] from Teacher t where t.student.id in (1,2); [其他解释] 1楼没看懂...应该是FROM Teachar 但是2楼和3楼的语句貌似不对啊， 你们这个语句好像查的是“教了张三或者李四的老师”...而不是并且 [其他解释] 按楼主的需求是在studenId=1中的又要存在于studenId=2中那么 from Teacher t where t.id in(select r.teacher.id from Relation r where r.student.id=1 and r.teacher.id in(select rt.teacher.id from Relation rt where r2.student.id=2)); [其他解释]
