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¼òµ¥²éѯ:
Query query = em.createQuery("SELECT c from Customer c");
return query.getResultList();
ÃüÃû²éѯ
@Entity
@NamedQuery(name = "findCustomerByName",
query = "SELECT c from Customer c
WHERE c.name
LIKE :name ")
·ÖÒ³:
query = em.createNamedQuery("findCustomerByName");
query.setParameter("name", "t,om");
query.setMaxResults(10);
query.setFirstResult(3);
List customers = query.getResultList();
ÉèÖòÎÊý:
SELECT o from Order i WHERE i.orderNo = ?1
query.setParameter(1, 100.00);
SELECT o from Order i WHERE o.price = :price
query.setParameter("price", 100.00);
µ¥¸öʵÌå¼ìË÷
query.getSingleResult();
²éѯ¼¯ºÏ:
WHERE c.orders IS EMPTY
WHERE CONCAT(c.fname, c.lname) = 't,om'
SELECT c.id, c.name from Customer c
¶à̬²éѯ
SELECT c from Customer c WHERE c.name LIKE :name
·Ö×é
SELECT o.customer, COUNT(o.id) from Order o
GROUP BY o.customer
ÅÅÐò
order by
×Ó²éѯ
SELECT o from Order I WHERE o.customer
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